https://invisible-island.net/dialog/

# dialog_lib(1)

## NAME

           dialog - widgets and utilities for the dialog program

## SYNOPSIS

           cc [ flag ... ] file ... -ldialog [ library ... ]
              or
           cc $(dialog-config --cflags) file ... $(dialog-config --libs) ]

           #include <dialog.h>

           Dialog is a program that will let you present a variety of questions or
           display messages using dialog boxes from a shell script.  It  is  built
           from  the  dialog library, which consists of several widgets as well as
           utility functions that are used by the widgets or the main program.

## DESCRIPTION

           This manpage documents the features from <dialog.h> which are likely to
           be  important to developers using the widgets directly.  Some hints are
           also given for developing new widgets.

           Here is a dialog version of Hello World:
                  int main(void)
                  {
                       int status;
                       init_dialog(stdin, stdout);
                       status = dialog_yesno(
                                 "Hello, in dialog-format",
                                 "Hello World!",
                                 0, 0);
                       end_dialog();
                       return status;
                  }

## DEFINITIONS

           Exit codes (passed back to the main program for its  use)  are  defined
           with  a  "DLG_EXIT_  prefix.   The efined constants can be mapped using
           environment variables as  described  in  dialog(1),  e.g.,  DLG_EXIT_OK
           corresponds to $DIALOG_OK.

           Useful  character  constants  which  correspond to user input are named
           with the "CHR_" prefix, e.g., CHR_BACKSPACE.

           Colors  and  video  attributes  are  categorized  and  associated  with
           settings  in the configuration file (see the discussion of $DIALOGRC in
           dialog(1)).   The  DIALOG_ATR(n)  macro  is  used  for   defining   the
           references to the combined color and attribute table dlg_color_table[].

           The dialog application passes its command-line parameters to the widget
           functions.  Some of those parameters are single values, but some of the
           widgets   accept   data   as   an   array  of  values.   Those  include
           checklist/radiobox, menubox and formbox.  When the  --item-help  option
           is  given,  an  extra column of data is expected.  The USE_ITEM_HELP(),
           CHECKBOX_TAGS, MENUBOX_TAGS and FORMBOX_TAGS macros are  used  to  hide
           this difference from the calling application.

           Most  of  the  other  definitions  found  in  <dialog.h>  are  used for
           convenience in building the library or  main  program.   These  include
           definitions based on the generated <dlg_config.h> header.

## DATA STRUCTURES

           All  of  the  global  data  for  the  dialog library is stored in a few
           structures:   DIALOG_STATE,   DIALOG_VARS   and   DIALOG_COLORS.    The
           corresponding  dialog_state,  dialog_vars  and  dlg_color_table  global
           variables should be initialized to zeros, and then populated  with  the
           data  to  use.   A  few  of these must be nonzero for the corresponding
           widgets to function.  As as the case  with  function  names,  variables
           beginning   with   "dialog_"  are  designed  for  use  by  the  calling
           application while variables beginning  with  "dlg_"  are  intended  for
           lower levels, e.g., by the dialog library.

## DIALOG_STATE

           The  state  variables  are  dialog's working variables.  It initializes
           those, uses them to manage the widgets.

### .all_subwindows

           This is a linked list of all subwindows created by  the  library.   The
           dlg_del_window  function  uses this to free storage for subwindows when
           deleting a window.

### .all_windows

           This is a linked list of all  windows  created  by  the  library.   The
           dlg_del_window  function  uses  this  to  locate  windows  which may be
           redrawn after deleting a window.

### .aspect_ratio

           This corresponds to  the  command-line  option  "--aspect-ratio".   The
           value  gives  the application some control over the box dimensions when
           using auto sizing (specifying 0 for height and width).   It  represents
           width  /  height.   The  default is 9, which means 9 characters wide to
           every 1 line high.

### .finish_string

           When set to true, this allows calls to dlg_finish_string to discard the
           corresponding data which is created to speed up layout computations for
           the given string parameter.  The gauge widget uses this feature.

### .getc_callbacks

           This is set up in ui_getc.c to record windows which must be polled  for
           input,  e.g.,  to  handle the background tailbox widget.  One window is
           designated as the foreground or control window.

### .getc_redirect

           If the control window for DIALOG_STATE.getc_callbacks  is  closed,  the
           list  is  transferred to this variable.  Closing all windows causes the
           application to exit.

### .had_resize

           This  is  set  to  TRUE  in  dlg_will_resize  or  dlg_result_key   when
           KEY_RESIZE is read, to tell dialog to ignore subsequent ERRs.

### .no_mouse

           This  corresponds  to  the  command-line option "--no-mouse".  If true,
           dialog will not initialize (and enable) the mouse in init_dialog.

### .output

           This is set in the dialog  application  to  the  stream  on  which  the
           application  and  library  functions  may write text results.  Normally
           that is the standard error, since the curses library prefers  to  write
           its data to the standard output.  Some scripts, trading portability for
           convenience, prefer to write results to the standard output,  e.g.,  by
           using the "--stdout" option.

### .output_count

           This  is incremented by dlg_does_output, which is called by each widget
           that writes text to the output.  The dialog application  uses  that  to
           decide    if    it    should    also    write    a   separator,   i.e.,
           DIALOG_STATE.separate_str, between calls to each widget.

### .pipe_input

           This is set in init_dialog to a stream which can be used by  the  gauge
           widget,  which  must  be  the application's standard input.  The dialog
           application calls init_dialog normally with input set to  the  standard
           input,  but  optionally  based  on  the "--input-fd" option.  Since the
           application cannot read from a pipe (standard input) and  at  the  same
           time  read  the curses input from the standard input, it must allow for
           reopening the  latter  from  either  a  specific  file  descriptor,  or
           directly  from  the terminal.  The adjusted pipe stream value is stored
           in this variable.

### .screen_height

           The text-formatting functions use this for the number of rows used  for
           formatting a string.

           It  is  used by dialog for the command-line options "--print-text-size"
           and "--print-text-only".

### .screen_initialized

           This is set in init_dialog and reset in  end_dialog.   It  is  used  to
           check  if  curses has been initialized, and if the endwin function must
           be called on exit.

### .screen_output

           This is set in init_dialog to the output  stream  used  by  the  curses
           library.   Normally that is the standard output, unless that happens to
           not be a  terminal  (and  if  init_dialog  can  successfully  open  the
           terminal directly).

### .screen_width

           The  text-formatting  functions use this for the number of columns used
           for formatting a string.

           It is used by dialog for the command-line  options  "--print-text-size"
           and "--print-text-only".

### .separate_str

           This  corresponds  to the command-line option "--separate-widget".  The
           given string specifies a  string  that  will  separate  the  output  on
           dialog's output from each widget.  This is used to simplify parsing the
           result of a dialog with several widgets.  If this option is not  given,
           the default separator string is a tab character.

### .tab_len

           This   corresponds  to  the  command-line  option  "--tab-len  number".
           Specify the number of spaces that  a  tab  character  occupies  if  the
           "--tab-correct" option is given.  The default is 8.

### .text_height

           The  text-formatting functions set this to the number of lines used for
           formatting a string.

           It is used by dialog for the command-line  options  "--print-text-size"
           and "--print-text-only".

### .text_only

           Dialog uses this in the command-line option "--print-text-only".

           The  text-formatting  functions  (dlg_print_text,  dlg_print_line,  and
           dlg_print_autowrap) check this to decide whether to print the formatted
           text to dialog's output or to the curses-display.

           Also,  dlg_auto_size  checks  the  flag,  allowing it to be used before
           init_dialog is called.

### .text_width

           The text-formatting functions set this to the number  of  columns  used
           for formatting a string.

           It  is  used by dialog for the command-line options "--print-text-size"
           and "--print-text-only".

### .trace_output

           This corresponds to the command-line option "--trace file".  It is  the
           file pointer to which trace messages are written.

### .use_colors

           This is set in init_dialog if the curses implementation supports color.

### .use_scrollbar

           This  corresponds  to  the command-line option "--scrollbar".  If true,
           draw a scrollbar to make windows holding scrolled data more readable.

### .use_shadow

           This corresponds to the command-line option "--no-shadow".  This is set
           in  init_dialog  if the curses implementation supports color.  If true,
           suppress shadows that would be drawn to the right and  bottom  of  each
           dialog box.

### .visit_items

           This  corresponds  to  the command-line option "--visit-items".  Modify
           the tab-traversal of the list-oriented widgets  (buildlist,  checklist,
           radiobox,  menubox,  inputmenu,  and  treeview)  to include the list of
           items as one of the states.  This is useful as a visual aid, i.e.,  the
           cursor position helps some users.

           The  dialog  application  resets  the dialog_vars data before accepting
           options to invoke each widget.  Most of the DIALOG_VARS members are set
           directly from dialog's command-line options:

## DIALOG_VARS

           In  contrast  to  DIALOG_STATE,  the  members of DIALOG_VARS are set by
           command-line options in dialog.

### .ascii_lines

           This corresponds to the command-line option "--ascii-lines.  It  causes
           line-drawing  to be done with ASCII characters, e.g., "+" and "-".  See
           DIALOG_VARS.no_lines.

### .backtitle

           This corresponds to the command-line  option  "--backtitle  backtitle".
           It specifies a backtitle string to be displayed on the backdrop, at the
           top of the screen.

### .beep_after_signal

           This corresponds to the command-line option "--beep-after".   If  true,
           beep  after  a  user  has  completed  a  widget  by pressing one of the
           buttons.

### .beep_signal

           This corresponds to the command-line option "--beep".  It is obsolete.

### .begin_set

           This is true if the command-line option "--begin y  x"  was  used.   It
           specifies  the position of the upper left corner of a dialog box on the
           screen.

### .begin_x

           This corresponds to the x value from the command-line option "--begin y
           x" (second value).

### .begin_y

           This corresponds to the y value from the command-line option "--begin y
           x" (first value).

### .cancel_label

           This corresponds to the command-line  option  "--cancel-label  string".
           The given string overrides the label used for "Cancel" buttons.

### .cant_kill

           This corresponds to the command-line option "--no-kill".  If true, this
           tells dialog to put the tailboxbg box in the background,  printing  its
           process  id  to dialog's output.  SIGHUP is disabled for the background
           process.

### .colors

           This corresponds to  the  command-line  option  "--colors".   If  true,
           interpret  embedded  "\Z" sequences in the dialog text by the following
           character, which tells dialog to set colors or video attributes:

           o   0 through 7 are the ANSI codes used in curses: black,  red,  green,
               yellow, blue, magenta, cyan and white respectively.

           o   Bold is set by 'b', reset by 'B'.

           o   Reverse is set by 'r', reset by 'R'.

           o   Underline is set by 'u', reset by 'U'.

           The  settings  are  cumulative, e.g., "\Zb\Z1" makes the following text
           bright red.  Restore normal settings with "\Zn".

### .column_separator

           This  corresponds  to  the  command-line  option  "--column-separator".
           Dialog splits data for radio/checkboxes and menus on the occurrences of
           the given string, and aligns the split data into columns.

### .cr_wrap

           This corresponds to the  command-line  option  "--cr-wrap".   If  true,
           interpret  embedded  newlines  in  the  dialog text as a newline on the
           screen.  Otherwise, dialog will only wrap lines  where  needed  to  fit
           inside  the  text  box.   Even  though you can control line breaks with
           this, dialog will still wrap any lines that are too long for the  width
           of  the box.  Without cr-wrap, the layout of your text may be formatted
           to look nice in the source code of your script  without  affecting  the
           way it will look in the dialog.

### .cursor_off_label

           This  corresponds  to the command-line option "--cursor-off-label".  If
           true, place the terminal cursor at the end of a button  instead  of  on
           the  first  character  of  the  button label.  This is useful to reduce
           visual confusion when the cursor coloration interacts poorly  with  the
           button-label text colors.

### .date_format

           This corresponds to the command-line option "--date-format string".  If
           the host provides strftime, and the  value  is  nonnull,  the  calendar
           widget uses this to format its output.

### .default_button

           This  is  set by the command-line option "--default-button.  It is used
           by dlg_default_button.

### .default_item

           This corresponds to the command-line  option  "--default-item  string".
           The  given  string  is used as the default item in a checklist, form or
           menu box.  Normally the first item in the box is the default.

### .defaultno

           This corresponds to the command-line option  "--defaultno".   If  true,
           make  the  default  value  of the yes/no box a No.  Likewise, treat the
           default button of widgets that provide "OK" and "Cancel" as  a  Cancel.
           If --no-cancel was given that option overrides this, making the default
           button always "Yes" (internally the same as "OK").

### .dlg_clear_screen

           This corresponds to the command-line option "--clear".  This option  is
           implemented  in the main program, not the library.  If true, the screen
           will be cleared on  exit.   This  may  be  used  alone,  without  other
           options.

### .erase_on_exit

           This  corresponds  to  the  command-line  option "--erase-on-exit".  If
           true, remove the dialog widget on  program  exit,  erasing  the  entire
           screen to its native background color, and place the terminal cursor at
           the lower left corner of the screen.

           This is useful for making the window contents invisible at the end of a
           series  of  dialog  boxes.   It can also be used at earlier stages of a
           series of invocations of dialog, if the series may be aborted before it
           is fully completed.

### .exit_label

           This corresponds to the command-line option "--exit-label string".  The
           given string overrides the label used for "EXIT" buttons.

### .extra_button

           This corresponds to the command-line option "--extra-button".  If true,
           some  widgets  show an extra button, between "OK" and "Cancel" buttons,
           or "Yes" and "No" buttons.

### .extra_label

           This corresponds to the  command-line  option  "--extra-label  string".
           The  given  string overrides the label used for "Extra" buttons.  Note:
           for inputmenu widgets, this defaults to "Rename".

### .formitem_type

           This is set by the command-line option  "--passwordform"  to  tell  the
           form  widget  that  its  text  fields  should  be treated like password
           widgets.

### .help_button

           This corresponds to the command-line option "--help-button".  If  true,
           some  widgets show a help-button after "OK" and "Cancel" buttons, i.e.,
           in checklist, radiolist and menu boxes, or the "Yes" and  "No"  buttons
           for the yesno box.

           If  --item-help  is  also  given, on exit the return status will be the
           same as for the "OK" button, and the item-help text will be written  to
           dialog's  output  after the token "HELP".  Otherwise, the return status
           will indicate that the Help button was pressed, and no message printed.

### .help_file

           This corresponds to the  command-line  option  "--hfile  string".   The
           given filename is passed to dialog_helpfile when the user presses F1.

### .help_label

           This corresponds to the command-line option "--help-label string".  The
           given string overrides the label used for "Help" buttons.

### .help_line

           This corresponds to the  command-line  option  "--hline  string".   The
           given  string  is  displayed  in  the  bottom of dialog windows, like a
           subtitle.

### .help_status

           This corresponds to the command-line option "--help-status".  If  true,
           and  the the help-button is selected, writes the checklist or radiolist
           information after the item-help "HELP" information.  This can  be  used
           to  reconstruct  the  state  of  a  checklist after processing the help
           request.

### .help_tags

           This corresponds to the command-line option  "--help-tags".   If  true,
           dlg_add_help_formitem  and  dlg_add_help_listitem  use  the  item's tag
           value consistently rather than using the  tag's  help-text  value  when
           DIALOG_VARS.item_help is set.

### .input_length

           This  is nonzero if DIALOG_VARS.input_result is allocated, versus being
           a pointer to the user's local variables.

### .input_menu

           This flag is set to denote whether the menubox widget implements a menu
           versus a inputmenu widget.

### .input_result

           This  may  be  either  a  user-supplied buffer, or a buffer dynamically
           allocated by the library, depending on DIALOG_VARS.input_length:

           o   If DIALOG_VARS.input_length is zero, this  is  a  pointer  to  user
               buffer (on the stack, or static).  The buffer size is assumed to be
               MAX_LEN, which is defined in <dialog.h>.

           o   When DIALOG_VARS.input_length is nonzero, this  is  a  dynamically-
               allocated buffer used by the widgets to return printable results to
               the calling application.

           Certain widgets copy a result to this buffer.  If the pointer is  NULL,
           or  if  the  length  is  insufficient  for  the result, then the dialog
           library  allocates  a  buffer  which  is   large   enough,   and   sets
           DIALOG_VARS.input_length.   Callers  should check for this case if they
           have supplied their own buffer.

### .insecure

           This corresponds to the command-line  option  "--insecure".   If  true,
           make  the  password  widget  friendlier  but  less  secure,  by echoing
           asterisks for each character.

### .in_helpfile

           This variable is used to prevent dialog_helpfile from showing anything,
           e.g., if F1 were pressed within a help-file display.

### .iso_week

           This  corresponds  to the command-line option "--iso-week".  It is used
           in the calendar widget to tell how to compute the starting week for the
           year:

           o   by  default, the calendar treats January 1 as the first week of the
               year.

           o   If this variable is true, the calendar uses ISO 8601's  convention.
               ISO 8601 numbers weeks starting with the first week in January with
               a Thursday in the current year.  January 1 may be in  the  previous
               year.

### .item_help

           This  corresponds  to  the command-line option "--item-help".  If true,
           interpret the tags data for checklist, radiolist and menu boxes  adding
           a  column whose text is displayed in the bottom line of the screen, for
           the currently selected item.

### .keep_tite

           This is set by the command-line option "--keep-tite" to tell dialog  to
           not  attempt  to  cancel  the  terminal  initialization (termcap ti/te)
           sequences  which  correspond  to  xterm's  alternate-screen  switching.
           Normally dialog does this to avoid flickering when run several times in
           a script.

### .keep_window

           This corresponds to the command-line option "--keep-window".  If  true,
           do  not  remove/repaint the window on exit.  This is useful for keeping
           the window contents visible when several widgets are run  in  the  same
           process.   Note  that  curses will clear the screen when starting a new
           process.

### .last_key

           This corresponds to the command-line option "--last-key".

### .max_input

           This corresponds to the command-line option "--max-input size".   Limit
           input strings to the given size.  If not specified, the limit is 2048.

### .no_hot_key

           This corresponds to the command-line option "--no-hot-list".

           Some   widgets   (buildlist,  checklist,  inputmenu,  menu,  radiolist,
           treeview) display a list for which the leading capital letter  in  each
           entry  is  accepted  as  a  hot-key,  to quickly move the focus to that
           entry.

           Setting this variable to TRUE disables the feature.

### .no_items

           This corresponds to the command-line option "--no-items".  Some widgets
           (checklist, inputmenu, radiolist, menu) display a list with two columns
           (a "tag" and "item", i.e., "description").  This tells dialog  to  read
           shorter rows from data, omitting the "list".

### .no_label

           This  corresponds  to the command-line option "--no-label string".  The
           given string overrides the label used for "No" buttons.

### .no_lines

           This corresponds to the command-line option "--no-lines.  It suppresses
           line-drawing.  See DIALOG_VARS.ascii_lines.

### .no_nl_expand

           This  corresponds  to  the  command-line  option  "--no-nl-expand".  If
           false, dlg_trim_string converts literal "\n" substrings  in  a  message
           into newlines.

### .no_tags

           This  corresponds to the command-line option "--no-tags".  Some widgets
           (checklist, inputmenu, radiolist, menu) display a list with two columns
           (a  "tag"  and "item", also known as "description").  The tag is useful
           for scripting, but may not help the user.  The --no-tags  option  (from
           Xdialog) may be used to suppress the column of tags from the display.

           Normally  dialog allows you to quickly move to entries on the displayed
           list, by matching a single character to the first character of the tag.
           When  the  --no-tags  option is given, dialog matches against the first
           character of the description.  In either case, the matchable  character
           is highlighted.

           Here is a table showing how the no_tags and no_items values interact:

           Widget      Fields Shown   Fields Read   .no_items   .no_tags
           --------------------------------------------------------------
           buildlist   item           tag,item          0          0*
           buildlist   item           tag,item          0          1
           buildlist   tag            tag               1          0*
           buildlist   tag            tag               1          1
           checklist   tag,item       tag,item          0          0
           checklist   item           tag,item          0          1
           checklist   tag            tag               1          0
           checklist   tag            tag               1          1
           inputmenu   tag,item       tag,item          0          0
           inputmenu   item           tag,item          0          1
           inputmenu   tag            tag               1          0
           inputmenu   tag            tag               1          1
           menu        tag,item       tag,item          0          0
           menu        item           tag,item          0          1
           menu        tag            tag               1          0
           menu        tag            tag               1          1
           radiolist   tag,item       tag,item          0          0
           radiolist   item           tag,item          0          1
           radiolist   tag            tag               1          0
           radiolist   tag            tag               1          1

           treeview    item           tag,item          0          0*
           treeview    item           tag,item          0          1
           treeview    tag            tag               1          0*
           treeview    tag            tag               1          1
           --------------------------------------------------------------

           * Xdialog  does  not display the tag column for the analogous buildlist
             and treeview widgets.  Dialog does  the  same  on  the  command-line.
             However  the library interface defaults to displaying the tag column.
             Your application can enable or disable the tag column as  needed  for
             each widget.

### .nocancel

           This  corresponds  to  the command-line option "--no-cancel".  If true,
           suppress the "Cancel" button in checklist, inputbox and menu box modes.
           A  script  can  still test if the user pressed the ESC key to cancel to
           quit.

### .nocollapse

           This corresponds to the command-line option "--no-collapse".   Normally
           dialog  converts tabs to spaces and reduces multiple spaces to a single
           space for text which is displayed in a message boxes,  etc.   It  true,
           that  feature  is  disabled.   Note  that  dialog will still wrap text,
           subject to the --cr-wrap option.

### .nook

           This corresponds to the  command-line  option  "--no-ok.   Dialog  will
           suppress the "ok" (or "yes") button from the widget.

### .ok_label

           This  corresponds  to the command-line option "--ok-label string".  The
           given string overrides the label used for "OK" buttons.

### .pause_secs

           When set, force dlg_set_timeout to  use  10  milliseconds  rather  than
           using the DIALOG_VARS.timeout_secs value.

### .print_siz

           This  corresponds  to the command-line option "--print-size".  If true,
           each widget prints its size to dialog's output when it is invoked.

### .quoted

           This corresponds to the command-line option "--quoted.  Normally dialog
           quotes  the  strings  returned  by checklist's as well as the item-help
           text.  If true, dialog will quote all string results.

### .reorder

           This corresponds to the command-line option  "--reorder.   By  default,
           the buildlist widget uses the same order for the output (right) list as
           for the input (left).  If true, dialog will use the order  in  which  a
           user adds selections to the output list.

### .separate_output

           This  corresponds  to  the command-line option "--separate-output".  If
           true, checklist widgets output result one  line  at  a  time,  with  no
           quoting.  This facilitates parsing by another program.

### .single_quoted

           This  corresponds  to  the  command-line  option "--single-quoted".  If
           true, use single-quoting as needed (and no quotes if unneeded) for  the
           output of checklist's as well as the item-help text.  If this option is
           not set, dialog uses  double  quotes  around  each  item.   The  latter
           requires  occasional  use  of  backslashes to make the output useful in
           shell scripts.

### .size_err

           This corresponds to the command-line  option  "--size-err".   If  true,
           check  the  resulting  size  of  a  dialog box before trying to use it,
           printing the resulting size if it is larger  than  the  screen.   (This
           option is obsolete, since all new-window calls are checked).

### .sleep_secs

           This  corresponds  to  the  command-line  option  "--sleep secs".  This
           option is implemented  in  the  main  program,  not  the  library.   If
           nonzero,  this is the number of seconds after to delay after processing
           a dialog box.

### .tab_correct

           This corresponds to the command-line option "--tab-correct".  If  true,
           convert  each  tab  character  of  the  text  to  one  or  more spaces.
           Otherwise,  tabs  are  rendered  according  to  the  curses   library's
           interpretation.

### .time_format

           This corresponds to the command-line option "--time-format string".  If
           the host provides strftime, and  the  value  is  nonnull,  the  timebox
           widget uses this to format its output.

### .timeout_secs

           This  corresponds  to  the  command-line  option  "--timeout secs".  If
           nonzero, timeout input requests (exit  with  error  code)  if  no  user
           response within the given number of seconds.

### .title

           This corresponds to the command-line option "--title title".  Specifies
           a title string to be displayed at the top of the dialog box.

### .trim_whitespace

           This  corresponds  to  the  command-line  option  "--trim".   If  true,
           eliminate  leading  blanks,  trim  literal newlines and repeated blanks
           from message text.

### .week_start

           This corresponds to the command-line option "--week-start".  It is used
           in  the  calendar  widget  to  set  the starting day for the week.  The
           string value can be

           o   a number (0 to 6, Sunday through Saturday using POSIX) or

           o   the special value "locale" (this works with  systems  using  glibc,
               providing  an  extension  to  the locale command, the first_weekday
               value).

           o   a string matching one of the abbreviations for the day of the  week
               shown in the calendar widget, e.g., "Mo" for "Monday".

### .yes_label

           This  corresponds to the command-line option "--yes-label string".  The
           given string overrides the label used for "Yes" buttons.

## WIDGETS

           Functions that  implement  major  functionality  for  the  command-line
           dialog program, e.g., widgets, have names beginning "dialog_".

           All dialog boxes have at least three parameters:

              title
                   the caption for the box, shown on its top border.

              height
                   the height of the dialog box.

              width
                   the width of the dialog box.

           Other parameters depend on the box type.

### dialog_buildlist

           implements the "--buildlist" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int list_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           char ** items
                is an array of strings which is viewed either as a list of rows
                tag item status

                or
                tag item status help

                depending on whether dialog_vars.item_help is set.

           int order_mode
                is reserved for future enhancements

### dialog_calendar

           implements the "--calendar" option.

           const char * title
                is the title on the top of the widget.

           const char * subtitle
                is the prompt text shown within the widget.

           int height
                is the height excluding the fixed-height calendar grid.

           int width
                is the overall width of the box,  which  is  adjusted  up  to  the
                calendar grid's minimum width if needed.

           int day
                is the initial day of the week shown, counting zero as Sunday.  If
                the value is negative, the current day of the week is used.

           int month
                is the initial month of the year shown, counting one  as  January.
                If the value is negative, the current month of the year is used.

           int year
                is  the initial year shown.  If the value is negative, the current
                year is used.

### dialog_checklist

           implements the "--checklist" and "--radiolist" options depending on the
           flag parameter.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int list_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           int items
                is an array of strings which is viewed either as a list of rows
                tag item status

                or
                tag item status help

                depending on whether dialog_vars.item_help is set.

           flag is  either  FLAG_CHECK,  for   checklists,   or   FLAG_RADIO   for
                radiolists.

### dialog_dselect

           implements the "--dselect" option.

           const char * title
                is the title on the top of the widget.

           const char * path
                is  the  preselected value to show in the input-box, which is used
                also to set the directory- and file-windows.

           int height
                is the height excluding the minimum needed to show the dialog  box
                framework.  If zero, the height is based on the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

### dialog_editbox

           implements the "--editbox" option.

           const char * title
                is the title on the top of the widget.

           const char * file
                is the name of the file from which to read.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is  the desired width of the box.  If zero, the height is adjusted
                to use the available screen size.

### dialog_form

           implements the "--form" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is  the desired width of the box.  If zero, the height is adjusted
                to use the available screen size.

           int form_height
                is the minimum height to reserve  for  displaying  the  list.   If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           int items
                is an array of strings which is viewed either as a list of rows
                Name NameY NameX Text TextY TextX FLen ILen

                or
                Name NameY NameX Text TextY TextX FLen ILen Help

                depending on whether dialog_vars.item_help is set.

### dialog_fselect

           implements the "--fselect" option.

           const char * title
                is the title on the top of the widget.

           const char * path
                is  the  preselected value to show in the input-box, which is used
                also to set the directory- and file-windows.

           int height
                is the height excluding the minimum needed to show the dialog  box
                framework.  If zero, the height is based on the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

### dialog_gauge

           implements  the  "--gauge"  option.   Alternatively,   a   simpler   or
           customized  gauge  widget  can  be  set  up  using  dlg_allocate_gauge,
           dlg_reallocate_gauge, dlg_update_gauge and dlg_free_gauge.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

           int percent
                is the percentage to show in the progress bar.

### dialog_inputbox

           implements the "--inputbox" or "--password" option,  depending  on  the
           value of password.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

           const char * init
                is  the initial value of the input box, whose length is taken into
                account when auto-sizing the width of the dialog box.

           int password
                if true, causes typed input to be echoed as asterisks.

### dialog_helpfile

           implements the "--hfile" option.

           const char * title
                is the title on the top of the widget.

           const char * file
                is the name of a  file  containing  the  text  to  display.   This
                function  is  internally  bound  to F1 (function key "1"), passing
                dialog_vars.help_file as a parameter.   The  dialog  program  sets
                that variable when the --hfile option is given.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

### dialog_menu

           implements  the  "--menu"  or "--inputmenu" option depending on whether
           dialog_vars.input_menu is set.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

           int menu_height
                is the minimum height to reserve  for  displaying  the  list.   If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           int items
                is an array of strings which is viewed either as a list of rows
                tag item

                or
                tag item help

                depending on whether dialog_vars.item_help is set.

### dialog_mixedform

           implements the "--mixedform" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int form_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           int items
                is an array of strings which is viewed either as a list of rows
                Name NameY NameX Text TextY TextX FLen ILen Ityp

                or
                Name NameY NameX Text TextY TextX FLen ILen Ityp Help

                depending on whether dialog_vars.item_help is set.

### dialog_mixedgauge

           implements the "--mixedgauge" option

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the caption text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

           int percent
                is the percentage to show in the progress bar.

           int item_no
                is the number of rows in items.

           int items
                is an array of strings which is viewed as a list of tag  and  item
                values.   The  tag  values are listed, one per row, in the list at
                the top of the widget.

                The item values are decoded: digits 0 through 9 are the  following
                strings

                0      Succeeded

                1      Failed

                2      Passed

                3      Completed

                4      Checked

                5      Done

                6      Skipped

                7      In Progress

                8      (blank)

                9      N/A

                A  string  with  a  leading "-" character is centered, marked with
                "%".  For example, "-75" is displayed as "75%".  Other strings are
                displayed as is.

### dialog_msgbox

           implements  the  "--msgbox"  or "--infobox" option depending on whether
           pauseopt is set.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

           int pauseopt
                if true, an "OK" button will be shown, and the  dialog  will  wait
                for  it  to  complete.   With  an  "OK"  button,  it  is denoted a
                "msgbox", without an "OK" button, it is denoted an "infobox".

### dialog_pause

           implements the "--pause" option.

           const char * title
                is the title on the top of the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

           int seconds
                is the timeout to use for the progress bar.

### dialog_prgbox

           implements the "--prgbox" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.  If empty or null,  no
                prompt is shown.

           const char * command
                is the name of the command to execute.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

           int pauseopt
                if  true,  an  "OK" button will be shown, and the dialog will wait
                for it to complete.

### dialog_progressbox

           implements the "--progressbox" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.  If empty or null,  no
                prompt is shown.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

### dialog_rangebox

           implements the "--rangebox" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is  the prompt text shown within the widget.  If empty or null, no
                prompt is shown.

           int height
                is the desired height of the widget.  If zero, the height is based
                on the screen size.

           int width
                is  the desired width of the widget.  If zero, the height is based
                on the screen size.

           int min_value
                is the minimum value to allow.

           int max_value
                is the maximum value to allow.

           int default_value
                is the default value, if no change is made.

### dialog_tailbox

           implements the "--tailbox" or "--tailboxbg" option depending on whether
           bg_task is set.

           const char * title
                is the title on the top of the widget.

           const char * file
                is the name of the file to display in the dialog.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

           int bg_task
                if true, the window is added to the callback list in dialog_state,
                and the application will  poll  for  the  window  to  be  updated.
                Otherwise  an  "OK"  button is added to the window, and it will be
                closed when the button is activated.

### dialog_textbox

           implements the "--textbox" option.

           const char * title
                is the title on the top of the widget.

           const char * file
                is the name of the file to display in the dialog.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is  the desired width of the box.  If zero, the height is based on
                the screen size.

### dialog_timebox

           implements the "--timebox" option.  See dlg_auto_size for layout  using
           height and width parameters.

           const char * title
                is the title on the top of the widget.

           const char * subtitle
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.

                o   If zero, the height is based on the screen size.

                o   If  greater  than  zero,  the requested height is added to the
                    minimum box size.

           int width
                is the desired width of the box.

                o   If zero, the height is based on the screen size.

                o   If greater than zero, the requested width  is  constrained  by
                    the minimum box size and the width of the buttons.

           int hour
                is  the initial hour shown.  If the value is negative, the current
                hour is used.  Returns DLG_EXIT_ERROR if the  value  specified  is
                greater than or equal to 24.

           int minute
                is  the  initial  minute  shown.   If  the  value is negative, the
                current minute is  used.   Returns  DLG_EXIT_ERROR  if  the  value
                specified is greater than or equal to 60.

           int second
                is  the  initial  second  shown.   If  the  value is negative, the
                current second is  used.   Returns  DLG_EXIT_ERROR  if  the  value
                specified is greater than or equal to 60.

### dialog_treeview

           implements the "--treeview" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

           int list_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           char ** items
                is the list of items,  contain  tag,  name,  and  optionally  help
                strings  (if dialog_vars.item_help is set).  The initial selection
                state for each item is also in this list.

           int flag

           flag is either FLAG_CHECK, for  checklists  (multiple  selections),  or
                FLAG_RADIO for radiolists (a single selection).

### dialog_yesno

           implements the "--yesno" option.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

## UTILITY FUNCTIONS

           Most   functions  that  implement  lower-level  functionality  for  the
           command-line dialog program or widgets, have  names  beginning  "dlg_".
           Bowing to longstanding usage, the functions that initialize the display
           and end it are named init_dialog and end_dialog.

           The only non-widget  function  whose  name  begins  with  "dialog_"  is
           dialog_version,  which  returns  the version number of the library as a
           string.

           A few functions are prefixed "_dlg_", because  they  are  required  for
           internal  use,  but  not  intended  as  part of the library application
           programming interface.

           Here is a brief summary of the utility functions and their parameters:

### dlg_add_callback

           Add a callback, used to  allow  polling  input  from  multiple  tailbox
           widgets.

           DIALOG_CALLBACK *p
                contains the callback information.

### dlg_add_callback_ref

           Like dlg_add_callback, but passes a reference to the DIALOG_CALLBACK as
           well as a pointer to a cleanup function which will be called  when  the
           associated input ends.

           DIALOG_CALLBACK **p
                points  to  the  callback information.  This is a reference to the
                pointer so that the caller's pointer  can  be  zeroed  when  input
                ends.

           DIALOG_FREEBACK func
                function   to  call  when  input  ends,  e.g.,  to  free  caller's
                additional data.

### dlg_add_help_formitem

           This is a utility function used enforce  consistent  behavior  for  the
           DIALOG_VARS.help_tags and DIALOG_VARS.item_help variables.

           int *result
                this  is updated to DLG_EXIT_ITEM_HELP if DIALOG_VARS.item_help is
                set.

           char **tag
                the tag- or help-text is stored here.

           DIALOG_FORMITEM *item
                contains the list item to use for tag- or help-text.

### dlg_add_help_listitem

           This is a utility function used enforce  consistent  behavior  for  the
           DIALOG_VARS.help_tags and DIALOG_VARS.item_help variables.

           int *result
                this  is updated to DLG_EXIT_ITEM_HELP if DIALOG_VARS.item_help is
                set.

           char **tag
                the tag- or help-text is stored here.

           DIALOG_LISTITEM *item
                contains the list item to use for tag- or help-text.

### dlg_add_last_key

           Report  the  last  key  entered  by  the  user.   This  implements  the
           --last-key command-line option, using dialog_vars.last_key.

           int mode
                controls  the  way  the  last  key  report is separated from other
                results:

                -2   (no separator)

                -1   (separator after the key name)

                0    (separator is optionally before the key name)

                1    (same as -1)

### dlg_add_quoted

           Add a quoted string to the result buffer (see dlg_add_result).   If  no
           quotes  are  necessary, none are used.  If dialog_vars.single_quoted is
           set, single-quotes are used.  Otherwise, double-quotes are used.

           char * string
                is the string to add.

### dlg_add_result

           Add a string to the result buffer dialog_vars.input_result.

           char * string
                is the string to add.

### dlg_add_separator

           Add an output-separator to the result buffer  dialog_vars.input_result.
           If  dialog_vars.output_separator  is  set,  use  that.   Otherwise,  if
           dialog_vars.separate_output is set, use newline.  If  neither  is  set,
           use a space.

### dlg_add_string

           Add   a   quoted   or   unquoted  string  to  the  result  buffer  (see
           dlg_add_quoted)   and    dlg_add_result),    according    to    whether
           dialog_vars.quoted is true.

           char * string
                is the string to add.

### dlg_align_columns

           Copy  and  reformat an array of pointers to strings, aligning according
           to the column separator  dialog_vars.column_separator.   If  no  column
           separator  is set, the array will be unmodified; otherwise it is copied
           and reformatted.

                  Caveat: This function is only implemented for 8-bit characters.

           char **target
                This is the array to reformat.  It points to the first  string  to
                modify.

           int per_row
                This is the size of the struct for each row of the array.

           int num_rows
                This is the number of rows in the array.

### dlg_allocate_gauge

           Allocates a gauge widget.  Use dlg_update_gauge to display the result.

           const char * title
                is the title string to display at the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int percent
                is the percentage to show in the progress bar.

### dlg_asciibox

           returns  its  parameter  transformed  to  the corresponding "+" or "-",
           etc., for the line-drawing characters used in dialog.  If the parameter
           is not a line-drawing or other special character such as ACS_DARROW, it
           returns 0.

           chtype ch
                is the parameter, usually one of the ACS_xxx constants.

### dlg_attr_clear

           Set window to the given attribute.

           WINDOW * win
                is the window to update.

           int height
                is the number of rows to update.

           int width
                is the number of columns to update.

           chtype attr
                is the attribute, e.g., A_BOLD.

### dlg_auto_size

           Compute window size based on the  size  of  the  formatted  prompt  and
           minimum dimensions for a given widget.

           Dialog  sets  dialog_state.text_height  and dialog_state.text_width for
           the formatted prompt as a side-effect.

           Normally dialog writes the formatted prompt to the curses  window,  but
           it   will   write   the  formatted  prompt  to  the  output  stream  if
           dialog_state.text_only is set.

           const char * title
                is the title string to display at the top of the widget.

           const char * prompt
                is the message text which will be displayed in  the  widget,  used
                here to determine how large the widget should be.

                If  the  value  is NULL, dialog allows the widget to use the whole
                screen, i.e., if the values referenced by height and/or width  are
                zero.

           int * height
                is the nominal height.  Dialog checks the referenced value and may
                update it:

                o   if the value is negative, dialog updates it to  the  available
                    height  of  the  screen,  after  reserving rows for the window
                    border  and  shadow,  as   well   as   taking   into   account
                    dialog_vars.begin_y and dialog_vars.begin_set.

                o   if the value is zero, dialog updates it to the required height
                    of the window, taking into  account  a  (possibly)  multi-line
                    prompt.

                o   if  the value is greater than zero, dialog uses it internally,
                    but restores the value on return.

           int * width
                is the nominal width.  Dialog checks the referenced value and  may
                update it:

                o   if  the  value is negative, dialog updates it to the available
                    width of the screen,  after  reserving  rows  for  the  window
                    border   and   shadow,   as   well   as  taking  into  account
                    dialog_vars.begin_x and dialog_vars.begin_set.

                o   if the value is zero, dialog updates it to the required  width
                    of  the  window,  taking  into account a (possibly) multi-line
                    prompt.

                o   if the value is greater than zero, dialog uses it  internally,
                    but restores the value on return.

           int boxlines
                is the number of lines to reserve in the vertical direction.

           int mincols
                is the minimum number of columns to use.

### dlg_auto_sizefile

           Like  dlg_auto_size,  but  use  a file contents to decide how large the
           widget should be.

           const char * title
                is the title string to display at the top of the widget.

           const char * file
                is the name of the file.

           int * height
                is the nominal height.

                If  it  is  -1,  use  the  screen's  height   (after   subtracting
                dialog_vars.begin_y if dialog_vars.begin_set is true).

                If  it  is  greater  than  zero, limit the referenced value to the
                screen-height after verifying that the file exists.

           int * width
                is the nominal width.

                If  it  is  -1,  use  the  screen's   width   (after   subtracting
                dialog_vars.begin_x if dialog_vars.begin_set is true).

                If  it  is  greater  than  zero, limit the referenced value to the
                screen-width after verifying that the file exists.

           int boxlines
                is the number of lines to reserve on the screen for drawing boxes.

           int mincols
                is the number of columns to reserve  on  the  screen  for  drawing
                boxes.

### dlg_beeping

           If  dialog_vars.beep_signal  is  nonzero, this calls beep once and sets
           dialog_vars.beep_signal to zero.

### dlg_boxchar

           returns its chtype parameter transformed as follows:

           o   if neither dialog_vars.ascii_lines nor dialog_vars.no_lines is set.

           o   if dialog_vars.ascii_lines is set, returns the corresponding "+" or
               "-", etc., for the line-drawing characters used in dialog.

           o   otherwise,  if dialog_vars.no_lines is set, returns a space for the
               line-drawing characters.

           o   if the parameter is not a line-drawing or other  special  character
               such as ACS_DARROW, it returns the parameter unchanged.

### dlg_box_x_ordinate

           returns   a   suitable  x-ordinate  (column)  for  a  new  widget.   If
           dialog_vars.begin_set is 1, use dialog_vars.begin_x;  otherwise  center
           the widget on the screen (using the width parameter).

           int width
                is the width of the widget.

### dlg_box_y_ordinate

           returns   a   suitable   y-ordinate   (row)   for  a  new  widget.   If
           dialog_vars.begin_set is 1, use dialog_vars.begin_y;  otherwise  center
           the widget on the screen (using the height parameter).

           int height
                is the height of the widget.

### dlg_buildlist

           This is an alternate interface to the buildlist widget which allows the
           application to read the list item states back directly without  putting
           them in the output buffer.

           const char * title
                is the title string to display at the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int list_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           DIALOG_LISTITEM * items
                is the list of items,  contain  tag,  name,  and  optionally  help
                strings  (if dialog_vars.item_help is set).  The initial selection
                state for each item is also in this list.

           const char * states
                This is a list of characters to  display  for  the  given  states.
                Normally a buildlist provides true (1) and false (0) values, which
                the  widget  displays  as  "*"  and   space,   respectively.    An
                application may set this parameter to an arbitrary null-terminated
                string.  The widget determines  the  number  of  states  from  the
                length  of  this  string, and will cycle through the corresponding
                display characters as the user presses the space-bar.

           int order_mode
                is reserved for future enhancements

           int * current_item
                The widget sets the  referenced  location  to  the  index  of  the
                current display item (cursor) when it returns.

### dlg_button_count

           Count the buttons in the list.

           const char ** labels
                is  a  list  of  (pointers  to) button labels terminated by a null
                pointer.

### dlg_button_key

           If a key was bound to one of the button-codes in dlg_result_key, fake a
           button-value and an "Cancel"  key to cause the calling widget to return
           the corresponding status.

           See dlg_ok_buttoncode, which maps settings for ok/extra/help and button
           number into exit-code.

### dlg_button_layout

           Make  sure there is enough space for the buttons by computing the width
           required for their labels, adding margins and  limiting  based  on  the
           screen size.

           const char ** labels
                is  a  list  of  (pointers  to) button labels terminated by a null
                pointer.

           int * limit
                the function sets the referenced limit to the width  required  for
                the buttons (limited by the screen size) if that is wider than the
                passed-in limit.

### dlg_button_sizes

           Compute the size of the button array in columns.

           const char ** labels
                is a list of (pointers to) button  labels  terminated  by  a  null
                pointer.

           int vertical
                is true if the buttons are arranged in a column rather than a row.

           int * longest
                Return the total number of columns in the referenced location.

           int * length
                Return the longest button's columns in the referenced location.

### dlg_button_to_char

           Find  the  first uppercase character in the label, which we may use for
           an abbreviation.  If the label is empty, return -1.   If  no  uppercase
           character   is   found,  return  0.   Otherwise  return  the  uppercase
           character.

           Normally  dlg_draw_buttons  and  dlg_char_to_button   use   the   first
           uppercase character.  However, they keep track of all of the labels and
           if the first has already been used in another label, they will continue
           looking  for  another uppercase character.  This function does not have
           enough information to make that check.

           const char * label
                is the label to test.

### dlg_button_x_step

           Compute the step-size needed between elements of the button array.

           const char ** labels
                is a list of (pointers to) button  labels  terminated  by  a  null
                pointer.

           int limit
                is the maximum number of columns to allow for the buttons.

           int * gap
                store  the nominal gap between buttons in the referenced location.
                This is constrained to be at least one.

           int * margin
                store the left+right total margins (for the list  of  buttons)  in
                the referenced location.

           int * step
                store the step-size in the referenced location.

### dlg_calc_list_width

           Calculate  the  minimum  width for the list, assuming none of the items
           are truncated.

           int item_no
                is the number of items.

           DIALOG_LISTITEM * items
                contains a name and text field, e.g., for checklists  or  radiobox
                lists.   The function returns the sum of the widest columns needed
                for of each of these fields.

                If dialog_vars.no_items is set, the text fields in  the  list  are
                ignored.

### dlg_calc_listh

           Calculate new height and list_height values.

           int * height
                on  input,  is  the  height  without  adding  the list-height.  On
                return, this contains the total  list-height  and  is  the  actual
                widget's height.

           int * list_height
                on  input, is the requested list-height.  On return, this contains
                the number of rows available for displaying the list after  taking
                into  account  the  screen  size and the dialog_vars.begin_set and
                dialog_vars.begin_y variables.

           int item_no
                is the number of items in the list.

### dlg_calc_listw

           This function is obsolete, provided for library-compatibility.   It  is
           replaced by dlg_calc_list_width.

           int item_no
                is the number of items.

           char ** items
                is a list of character pointers.

           int group
                is  the  number  of  items  in  each group, e.g., the second array
                index.

### dlg_char_to_button

           Given a list of button  labels,  and  a  character  which  may  be  the
           abbreviation  for  one, find it, if it exists.  An abbreviation will be
           the first character which happens to be capitalized in the  label.   If
           the  character  is  found,  return its index within the list of labels.
           Otherwise, return DLG_EXIT_UNKNOWN.

           int ch
                is the character to find.

           const char ** labels
                is a list of (pointers to) button  labels  terminated  by  a  null
                pointer.

### dlg_checklist

           This  entrypoint  provides the --checklist or --radiolist functionality
           without the limitations of dialog's  command-line  syntax  (compare  to
           dialog_checklist).

           const char * title
                is the title string to display at the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int list_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of items.

           DIALOG_LISTITEM * items
                This is a list of the items to display in the checklist.

           const char * states
                This is a list of characters to  display  for  the  given  states.
                Normally a checklist provides true (1) and false (0) values, which
                the  widget  displays  as  "*"  and   space,   respectively.    An
                application may set this parameter to an arbitrary null-terminated
                string.  The widget determines  the  number  of  states  from  the
                length  of  this  string, and will cycle through the corresponding
                display characters as the user presses the space-bar.

           int flag
                This is should be one of FLAG_CHECK or  FLAG_RADIO,  depending  on
                whether the widget should act as a checklist or radiobox.

           int * current_item
                The  widget  sets  the  referenced  location  to  the index of the
                current display item (cursor) when it returns.

### dlg_check_scrolled

           given a function key (or other key that was mapped to a function  key),
           check if it is one of the up/down scrolling functions:

                  DLGK_PAGE_FIRST,
                  DLGK_PAGE_LAST,
                  DLGK_GRID_UP,
                  DLGK_GRID_DOWN,
                  DLGK_PAGE_PREV or
                  DLGK_PAGE_NEXT.

           Some  widgets  use  these key bindings for scrolling the prompt-text up
           and down, to allow for display in very small windows.

           The function returns 0 (zero) if it finds one of these keys, and -1  if
           not.

           int key
                is the function-key to check

           int last
                is the number of lines which would be used to display the scrolled
                prompt in an arbitrarily tall window.  It is used  here  to  check
                limits for the offset value.

           int page
                this  is  the available height for writing scrolled text, which is
                smaller than the window if it contains buttons.

           bool * show
                on return, holds TRUE if  dlg_print_scrolled  should  be  used  to
                redisplay the prompt text.

           int * offset
                on entry, holds the starting line number (counting from zero) last
                used  for  dlg_print_scrolled.   On  return,  holds  the   updated
                starting line number.

### dlg_clear

           Set  window to the default dialog screen attribute.  This is set in the
           rc-file with screen_color.

### dlg_clr_result

           Free storage used for  the  result  buffer  (dialog_vars.input_result).
           The corresponding pointer is set to NULL.

### dlg_color_count

           Return the number of colors that can be configured in dialog.

### dlg_color_setup

           Initialize the color pairs used in dialog.

### dlg_count_argv

           Count the entries in an argument vector.

           argv Points to the argument vector.

### dlg_count_columns

           Returns  the  number  of  columns  used  for  a  string.   This  is not
           necessarily the number of bytes in a string.

           const char * string
                is the string to measure.

### dlg_count_real_columns

           Returns the number of columns used for a string,  accounting  for  "\Z"
           sequences which can be used for coloring the text if dialog_vars.colors
           is set.  This is not necessarily the number of bytes in a string.

           const char * string
                is the string to measure.

### dlg_count_wchars

           Returns the number of wide-characters in the string.

           const char * string
                is the string to measure.

### dlg_create_rc

           Create a configuration file, i.e., write  internal  tables  to  a  file
           which can be read back by dialog as an rc-file.

           const char * filename
                is the name of the file to write to.

### dlg_ctl_size

           If  dialog_vars.size_err is true, check if the given window size is too
           large to fit on the screen.  If so, exit with an  error  reporting  the
           size of the window.

           int height
                is the window's height

           int width
                is the window's width

### dlg_default_button

           If  dialog_vars.default_button is positive, return the button-index for
           that button code, using dlg_ok_buttoncode to test indices starting with
           zero.  Otherwise (or if no match was found for the button code), return
           zero.

### dlg_default_formitem

           If dialog_vars.default_item is not null, find that name by matching the
           name  field  in  the list of form items.  If found, return the index of
           that item in the list.  Otherwise, return zero.

           DIALOG_FORMITEM * items
                is the list of items to search.  It is terminated by an entry with
                a null name field.

### dlg_default_item

           This  function  is obsolete, provided for library-compatibility.  It is
           replaced by dlg_default_formitem and dlg_default_listitem.

           char ** items
                is the list of items to search.

           int llen
                is the number of items in  each  group,  e.g.,  the  second  array
                index.

### dlg_defaultno_button

           If dialog_vars.defaultno is true, and dialog_vars.nocancel is not, find
           the button-index for the "Cancel" button.  Otherwise, return the  index
           for "OK" (always zero).

### dlg_del_window

           Remove a window, repainting everything else.

           WINDOW * win
                is the window to remove.

### dlg_der_window

           create a derived window, e.g., for an input area of a widget

           WINDOW * win
                is the parent window

           int height
                is the subwindow's height

           int width
                is the subwindow's width

           int y
                is the subwindow's top-row

           int x
                is the subwindow's left-column

### dlg_does_output

           This  is  called each time a widget is invoked which may do output.  It
           increments dialog_state.output_count, so the output function in  dialog
           can test this and add a separator.

### dlg_draw_arrows

           Draw  up/down arrows on a window, e.g., for scrollable lists.  It calls
           dlg_draw_arrows2  using  the  menubox_color  and   menubox_border_color
           attributes.

           WINDOW * dialog
                is the window on which to draw an arrow.

           int top_arrow
                is true if an up-arrow should be drawn at the top of the window.

           int bottom_arrow
                is  true  if  an  down-arrow  should be drawn at the bottom of the
                window.

           int x
                is the zero-based column  within  the  window  on  which  to  draw
                arrows.

           int top
                is the zero-based row within the window on which to draw up-arrows
                as well as a horizontal line to show the window's top.

           int bottom
                is the zero-based row within the window on  which  to  draw  down-
                arrows as well as a horizontal line to show the window's bottom.

### dlg_draw_arrows2

           Draw up/down arrows on a window, e.g., for scrollable lists.

           WINDOW * dialog
                is the window on which to draw an arrow.

           int top_arrow
                is true if an up-arrow should be drawn at the top of the window.

           int bottom_arrow
                is  true  if  an  down-arrow  should be drawn at the bottom of the
                window.

           int x
                is the zero-based column  within  the  window  on  which  to  draw
                arrows.

           int top
                is the zero-based row within the window on which to draw up-arrows
                as well as a horizontal line to show the window's top.

           int bottom
                is the zero-based row within the window on  which  to  draw  down-
                arrows as well as a horizontal line to show the window's bottom.

           chtype attr
                is the window's background attribute.

           chtype borderattr
                is the window's border attribute.

### dlg_draw_bottom_box

           Draw  a  partial box at the bottom of a window, e.g., to surround a row
           of buttons.  It is designed to merge with an existing  box  around  the
           whole  window  (see  dlg_draw_box), so it uses tee-elements rather than
           corner-elements on the top corners of this box.

           WINDOW * win
                is the window to update.

### dlg_draw_bottom_box2

           Draw a partial box at the bottom of a window, e.g., to surround  a  row
           of  buttons.   It  is designed to merge with an existing box around the
           whole window (see dlg_draw_box2), so it uses tee-elements  rather  than
           corner-elements on the top corners of this box.

           WINDOW * win
                is the window to update.

           chtype on_left
                is  used  to color the upper/left edges of the box, i.e., the tee-
                element and horizontal line

           chtype on_right
                is used to color the right edge of the box, i.e., the tee-element

           chtype on_inside
                is used to fill-color the inside of the box

### dlg_draw_box

           Draw a rectangular box with line drawing characters.

           WINDOW * win
                is the window to update.

           int y
                is the top row of the box.

           int x
                is the left column of the box.

           int height
                is the height of the box.

           int width
                is the width of the box.

           chtype boxchar
                is used to color the right/lower edges.   It  also  is  fill-color
                used for the box contents.

           chtype borderchar
                is used to color the upper/left edges.

### dlg_draw_box2

           Draw a rectangular box with line drawing characters.

           WINDOW * win
                is the window to update.

           int y
                is the top row of the box.

           int x
                is the left column of the box.

           int height
                is the height of the box.

           int width
                is the width of the box.

           chtype boxchar
                is used to fill-color for the box contents.

           chtype borderchar
                is used to color the upper/left edges.

           chtype borderchar2
                is used to color the right/lower edges.

### dlg_draw_buttons

           Print a list of buttons at the given position.

           WINDOW * win
                is the window to update.

           int y
                is the starting row.

           int x
                is the starting column.

           const char ** labels
                is  a  list  of  (pointers  to) button labels terminated by a null
                pointer.

           int selected
                is the index within the list of the selected button.

           int vertical
                is true if the buttons are arranged in a column rather than a row.

           int limit
                is the number of columns (or rows if  vertical)  allowed  for  the
                display.

### dlg_draw_helpline

           draw  the  text  in  dialog_vars.help_line  at  the bottom of the given
           window.

           WINDOW * dialog
                is the window to modify.

           bool decorations
                if true, allow room for the scrolling arrows.

### dlg_draw_scrollbar

           If dialog_state.use_scrollbar is set, draw a  scrollbar  on  the  right
           margin  of  windows  holding scrollable data.  Also (whether or not the
           scrollbar is drawn), annotate the bottom margin of the window with  the
           percentage   of   data   by   the  bottom  of  that  window,  and  call
           dlg_draw_arrows2 to put markers on the window showing when more data is
           available.

           WINDOW * win
                is the window in which the data is scrolled.  Because left, right,
                top, bottom are passed as  parameters,  this  window  can  contain
                additional data.

           long first_data
                is  the  zero-based  index to the first row of data in the current
                window.

           long this_data
                is the zero-based index to the current row of data.

           long next_data
                is the zero-based index to the next data after the current row.

           long total_data
                is the total number of rows of data.

           int left
                is the zero-based left margin/column of the window.   The  up/down
                arrows are draw inset by 5 columns from this point.

           int right
                is   the  zero-based  right  margin/column  of  the  window.   The
                scrollbar is drawn flush against this column.

           int top
                is the zero-based row within the window on which to draw up-arrows
                as well as a horizontal line to show the window's top.

           int bottom
                is  the  zero-based  row  within the window on which to draw down-
                arrows as well as a horizontal line to show the window's bottom.

           chtype attr
                is the window's background attribute.

           chtype borderattr
                is the window's border attribute.

### dlg_draw_shadow

           Draw shadows along the right and bottom edge of a window to give  it  a
           3-dimensional  look.   (The  height,  etc.,  may not be the same as the
           window's actual values).

           WINDOW * win
                is the window to update.

           int height
                is the height of the window.

           int width
                is the width of the window.

           int y
                is the top row of the window.

           int x
                is the left column of the window.

### dlg_draw_title

           Draw a title centered at the top of the window.

           WINDOW * win
                is the window to update.

           const char * title
                is the title string to display at the top of the widget.

### dlg_dummy_menutext

           This is a utility function which supports the --inputmenu option of the
           dialog  program.   If dialog_vars.input_menu is set, dialog_menu passes
           this pointer to dlg_menu as the rename_menutext parameter.   Otherwise,
           it passes dlg_dummy_menutext.

           The function should only return DLG_EXIT_ERROR.

           DIALOG_LISTITEM * items
                is the list of menu items

           int current
                is the index of the currently-selected item

           char * newtext
                is the updated text for the menu item

### dlg_dump_keys

           Write  all user-defined key-bindings to the given stream, e.g., as part
           of dlg_create_rc.

           FILE * fp
                is the stream on which to write the bindings.

### dlg_dump_window_keys

           Write all user-defined key-bindings to the given stream, e.g., as  part
           of dlg_create_rc.

           FILE * fp
                is the stream on which to write the bindings.

           WINDOW * win
                is the window for which bindings should be dumped.  If it is null,
                then only built-in bindings are dumped.

### dlg_eat_argv

           Remove one or more items from an argument vector.

           int * argcp
                in/out parameter giving the length of the argument  vector.   char
                ***  argvp  in/out parameter pointing to the argument vector.  int
                start starting index.  int count number of arguments to remove.

### dlg_edit_offset

           Given the character-offset in the string,  returns  the  display-offset
           where dialog should position the cursor.  In this context, "characters"
           may be multicolumn, since the  string  can  be  a  multibyte  character
           string.

           char * string
                is the string to analyze

           int offset
                is the character-offset

           int x_last
                is  a  limit  on  the column positions that can be used, e.g., the
                window's size.

### dlg_edit_string

           Updates  the  string  and  character-offset,  given   various   editing
           characters  or  literal characters which are inserted at the character-
           offset.  Returns true if an editing change was made  (and  the  display
           should  be updated), and false if the key was something like KEY_ENTER,
           which is a non-editing action outside this function.

           char * string
                is the (multibyte) string to update

           int * offset
                is the character-offset

           int key
                is the editing key

           int fkey
                is true if the editing key is a function-key

           bool force
                is used in a special loop case by calling code to force the return
                value of this function when a function-key code 0 is passed in.

### dlg_exit

           Given  an  internal  exit  code, check if the corresponding environment
           variable is set.  If so, remap the exit code to match  the  environment
           variable.  Finally call exit with the resulting exit code.

           int code
                is  the  internal  exit  code,  e.g.,  DLG_EXIT_OK,  which  may be
                remapped.

           The dialog program uses this function to allow shell scripts  to  remap
           the exit codes so they can distinguish ESC from ERROR.

### dlg_exitcode2s

           Returns the name of an exit-code, e.g., "OK" for DLG_EXIT_OK.

           int code
                is an exit-code for dialog as defined in <dialog.h>.

### dlg_exitname2n

           Returns  an  exit-code  as  the  reverse  of  dlg_exitcode2n,  e.g.,  0
           (DLG_EXIT_OK) for the "OK" string.

           const char * name
                is the name of an exit-code for dialog as  defined  in  <dialog.h>
                but omitting the "DLG_EXIT_" prefix.

### dlg_exit_buttoncode

           Map the given button index for dlg_exit_label into dialog's exit-code.

           int button
                is the button index

### dlg_exit_label

           Return  a  list of button labels.  If dialog_vars.extra_button is true,
           return the result of dlg_ok_labels.  Otherwise, return a list with  the
           "Exit"  label and (if dialog_vars.help_button is set) the "Help" button
           as well.

### dlg_exiterr

           Quit program killing all tailboxbg widgets.

           const char * fmt
                is the format of the printf-like message to write.

           ...
                are the variables to apply to the fmt format.

### dlg_find_index

           Given  the  character-offset  to  find  in   the   list,   return   the
           corresponding array index.

           const int *list
                contains  a list of character-offsets, i.e., indices into a string
                that denote the beginning of multibyte characters.

           int limit
                is the last index into list to search.

           int to_find
                is the character-offset to find.

### dlg_finish_string

           If DIALOG_STATE.finish_string is true, this function discards data used
           to speed up layout computations.

           const char * string
                is  the address of the string whose data should be discarded.  The
                address rather than contents is  used  as  the  unique  identifier
                because some of the caching is used for editable input-fields.

### dlg_flush_getc

           Cancel the local data saved by dlg_last_getc.

### dlg_editbox

           This  entrypoint  provides  the  --editbox  functionality  without  the
           limitations   of   dialog's    command-line    syntax    (compare    to
           dialog_editbox).

           const char * title
                is the title string to display at the top of the widget.

           char *** list
                is  a  pointer  to  an  array  of  char *  pointers.  The array is
                allocated by the caller, and  so  are  the  strings  to  which  it
                points.  The dlg_editbox function may reallocate the array and the
                strings.

           int * rows
                points to the nominal length of list.   The  referenced  value  is
                updated iflist is reallocated.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

### dlg_form

           This   entrypoint   provides   the  --form  functionality  without  the
           limitations of dialog's command-line syntax (compare to dialog_form).

           const char * title
                is the title string to display at the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is  the desired width of the box.  If zero, the height is adjusted
                to use the available screen size.

           int form_height
                is the minimum height to reserve  for  displaying  the  list.   If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of items.

           DIALOG_FORMITEM * items
                This is a list of the items to display in the form.

           int * current_item
                The  widget  sets  the  referenced  location  to  the index of the
                current display item (cursor) when it returns.

### dlg_free_columns

           Free data allocated by dlg_align_columns.

           char **target
                This is the array which was reformatted.  It points to  the  first
                string to free.

           int per_row
                This is the size of the struct for each row of the array.

           int num_rows
                This is the number of rows in the array.

### dlg_free_formitems

           Free memory owned by a list of DIALOG_FORMITEM's.

           DIALOG_FORMITEM * items
                is the list to free.

### dlg_free_gauge

           Remove the gauge widget from the screen and free its associated memory.

           void *objptr
                points to the gauge widget.

### dlg_getc

           Read  a  character  from  the given window.  Handle repainting here (to
           simplify  things  in  the  calling  application).   Also,   if   input-
           callback(s)  are  set  up,  poll the corresponding files and handle the
           updates, e.g., for displaying a tailbox.  Returns the key-code.

           WINDOW * win
                is the window within which to read.

           int * fkey
                as a side-effect, set this to true if the  key-code  is  really  a
                function-key.

### dlg_getenv_num

           Get a number from the environment:

           o   If  the  caller  provides a pointer in the second parameter, return
               success/failure for the function return, and the actual  value  via
               the  pointer.   Use  this  for  decoding  arbitrary  numbers, e.g.,
               negative or zero.

           o   If the caller does not provide a pointer, return the decoded  value
               for  the  function-return.   Use this when only values greater than
               zero are useful.

           char * name
                is the name of the environment-variable to retrieve.

           int * value
                is the optional pointer to a return-value.

### dlg_getenv_str

           Get a string from the environment, rejecting those which  are  entirely
           blank.

           char * name
                is the name of the environment-variable to retrieve.

### dlg_get_attrs

           extract the video attributes from the given window.

           WINDOW * win
                is the window from which to get attributes.

### dlg_getc_callbacks

           passes the given key-code ch to the current window that has established
           a callback.  If the callback returns zero, remove it and try  the  next
           window.   If  no  more callbacks remain, return.  If any callbacks were
           found, return true, otherwise false.

           int ch
                is the key-code

           int fkey
                is true if the key is a function-key

           int * result
                is used to pass an exit-code to the caller, which should pass that
                via dlg_exit.

### dlg_index_columns

           Build  a  list  of the display-columns for the given multibyte string's
           characters.

           const char * string
                is the string to analyze

### dlg_index_wchars

           Build an index of the wide-characters in the string, so the caller  can
           easily tell which byte-offset begins a given wide-character.

           const char * string
                is the string to analyze

### dlg_item_help

           Draw the string for the dialog_vars.item_help feature.

           const char * txt
                is the help-message

### dlg_keep_tite

           This  performs  the check and modifications for the command-line option
           "--keep-tite", used in init_dialog as  well  as  for  the  command-line
           option --erase-on-exit.

           FILE * output
                is  the  output  stream used for displaying widgets.  It is either
                stdout or stderr, depending on the --stdout option.

### dlg_killall_bg

           If dialog has callbacks active, purge the list  of  all  that  are  not
           marked  to  keep  in  the  background.   If  any remain, run those in a
           background process.

           int * retval
                stores the exit-code to pass back to the caller.

### dlg_last_getc

           returns the most recent character that was read via dlg_getc.

### dlg_limit_columns

           Given a column limit, count the number of wide characters that can  fit
           into  that  limit.  The offset is used to skip over a leading character
           that was already written.

           const char * string
                is the string to analyze

           int limit
                is the column limit

           int offset
                is the starting offset from which analysis should continue

### dlg_lookup_key

           Check for a key-binding.  If there is no binding  associated  with  the
           widget,  it simply returns the given curses-key.  Otherwise, it returns
           the result of the binding

           WINDOW * win
                is the window on which the binding is checked

           int curses_key
                is the curses key-code

           int * dialog_key
                is the corresponding dialog internal code  (see  DLG_KEYS_ENUM  in
                dlg_key.h).

### dlg_max_input

           Limit the parameter according to dialog_vars.max_input

           int max_len
                is  the  value to limit.  If it is less than or equal to zero, the
                return value is the maximum value for dialog_vars.max_input.

### dlg_match_char

           Match a given character against the beginning of the  string,  ignoring
           case  of  the  given character.  The matching string must begin with an
           uppercase character.

           int ch
                is the character to check

           const char * string
                is the string to search

### dlg_menu

           This  entrypoint  provides  the  --menu   functionality   without   the
           limitations of dialog's command-line syntax (compare to dialog_menu).

           const char * title
                is the title string to display at the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int menu_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of items.

           DIALOG_LISTITEM * items
                This is a list of the items to display in the form.

           int * current_item
                The widget sets the  referenced  location  to  the  index  of  the
                current display item (cursor) when it returns.

           DIALOG_INPUTMENU rename_menutext
                If  this  is  not  dlg_dummy_menutext,  the  widget  acts  like an
                inputmenu  widget,  providing  an  extra  "Rename"  button,  which
                activates an edit feature on the selected menu item.

### dlg_move_window

           Moves/resizes the given window to the given position and size.

           WINDOW *win
                is the window to move/resize.

           WINDOW *height
                is the height of the resized window.

           WINDOW *width
                is the width of the resized window.

           WINDOW *y
                y-ordinate to use for the repositioned window.

           WINDOW *x
                x-ordinate to use for the repositioned window.

### dlg_mouse_bigregion

           Retrieve the big-region under the pointer.

           int y
                is the row on which the mouse click occurred

           int x
                is the column on which the mouse click occurred

### dlg_mouse_free_regions

           Free the memory associated with mouse regions.

### dlg_mouse_mkbigregion

           Creates  a  region  on  which  the mouse-clicks will return a specified
           code.

           int y
                is the top-row of the region.

           int x
                is the left-column of the region.

           int height
                is the height of the region.

           int width
                is the width of the region.

           int code
                is a code used to make the region unique within a widget

           int step_x
                is used in modes 2 (columns) and 3 (cells) to determine the  width
                of a column/cell.

           int step_y
                is currently unused

           int mode
                is  used  to determine how the mouse position is translated into a
                code (like a function-key):

                1  index by lines

                2  index by columns

                3  index by cells

### dlg_mouse_mkregion

           int y
                is the top-row of the region.

           int x
                is the left-column of the region.

           int height
                is the height of the region.

           int width
                is the width of the region.

           int code
                is a code used to make the region unique within a widget

### dlg_mouse_region

           Retrieve the frame under the mouse pointer

           int y
                is the row of the mouse-click

           int x
                is the column of the mouse-click

### dlg_mouse_setbase

           Sets a base for subsequent calls to  dlg_mouse_mkregion,  so  they  can
           make regions relative to the start of a given window.

           int x
                is the left-column for the base

           int y
                is the top-row for the base

### dlg_mouse_setcode

           Sets  a  value  used internally by dlg_mouse_mkregion which is added to
           the code parameter.  By providing different values, e.g., multiples  of
           KEY_MAX,  it is possible to support multiple "big" regions in a widget.
           The buildlist widget uses this feature to recognize mouse-clicks in the
           left/right panes.

           int code
                is the value to add to dlg_mouse_mkregion's code parameter.

### dlg_mouse_wgetch

           is  a wrapper for dlg_getc which additionally maps mouse-clicks (if the
           curses library supports those) into extended function-keys which encode
           the  position  according to the mode in dlg_mouse_mkbigregion.  Returns
           the corresponding key-code.

           WINDOW * win
                is the window on which to perform the input

           int * fkey
                the referenced location is set to  true  if  the  key-code  is  an
                actual or extended (mouse) function-key.

### dlg_mouse_wgetch_nowait

           This is a non-blocking variant of dlg_mouse_wgetch.

           WINDOW * win
                is the window on which to perform the input

           int * fkey
                the  referenced  location  is  set  to  true if the key-code is an
                actual or extended (mouse) function-key.

### dlg_need_separator

           Check     if     an      output-separator      is      needed.       If
           dialog_vars.output_separator   is  set,  return  true.   Otherwise,  if
           dialog_vars.input_result is nonempty, return true.  If neither,  return
           false.

### dlg_new_modal_window

           Create a modal window, optionally with a shadow.  The shadow is created
           if dialog_state.use_shadow is true.

           WINDOW * parent
                is the parent window (usually the top-level window of a widget)

           int height
                is the window's height

           int width
                is the window's width

           int y
                is the window's top-row

           int x
                is the window's left-column

### dlg_new_window

           Create a window, optionally with a shadow.  The shadow  is  created  if
           dialog_state.use_shadow is true.

           int height
                is the window's height

           int width
                is the window's width

           int y
                is the window's top-row

           int x
                is the window's left-column

### dlg_next_button

           Return the next index in the list of labels.

           const char ** labels
                is  a  list  of  (pointers  to) button labels terminated by a null
                pointer.

           int button
                is the current button-index.

### dlg_next_ok_buttonindex

           Assuming that the caller is using dlg_ok_labels to list  buttons,  find
           the next index in the list of buttons.

           int current
                is the current index in the list of buttons

           int extra
                if negative, provides a way to enumerate extra active areas on the
                widget.

### dlg_ok_buttoncode

           Map the given button index for dlg_ok_labels into dialog's exit-code.

           int button
                is the button-index (which is not  necessarily  the  same  as  the
                index in the list of labels).

### dlg_ok_button_key

           Calls  dlg_button_key  with the "Cancel" button disabled, e.g., for the
           textbox widget.

### dlg_ok_label

           Returns a list with the "Ok" label, and if  dialog_vars.help_button  is
           true, the "Help" label as well.

### dlg_ok_labels

           Return a list of button labels for the OK/Cancel group of widgets.

### dlg_ordinate

           Decode the string as an integer, decrement if greater than zero to make
           a curses-ordinate from a dialog-ordinate.

### dlg_parse_bindkey

           Parse the parameters of the "bindkeys" configuration-file entry.   This
           expects widget name which may be "*", followed by curses key definition
           and then dialog key definition.

           char * params
                is the parameter string to parse.

### dlg_parse_rc

           Parse the configuration file and set up variables.

### dlg_popen

           Open a pipe which ties the standard error  and  output  together.   The
           popen function captures only the standard output of a command.

           const char *command
                The shell command to run.

           const char *type
                Like popen, "r" is used to read, and "w" is used to write.

### dlg_prev_button

           Return the previous index in the list of labels.

           const char ** labels
                is  a  list  of  (pointers  to) button labels terminated by a null
                pointer.

           int button
                is the current button index

### dlg_print_line

           Print one line of the prompt in the window within  the  limits  of  the
           specified  right  margin.   The  line will end on a word boundary and a
           pointer to the start of the next line is returned, or a NULL pointer if
           the end of *prompt is reached.

           WINDOW *win
                is the window to update.

           chtype *attr
                holds the starting attributes, and is updated to reflect the final
                attributes applied to the string.

           const char *prompt
                is the string to print

           int lm
                is the left margin.

           int rm
                is the right margin

           int *x
                returns the ending x-ordinate.

### dlg_print_listitem

           This is a helper function used for the various  "list"  widgets,  e.g.,
           checklist,  menu,  buildlist, treeview.  Each list-widget has "tag" and
           "description"  values  for  each  item  which  can  be  displayed.   If
           dialog_vars.no_tags  is  true, the "tag" value is not shown.  The first
           character of the first value shown (tag or description) is  highlighted
           to indicate that the widget will match it for quick navigation.

           WINDOW *win
                the window in which to display the text

           const char *text
                the value to display

           int climit
                the number of columns available for printing the text

           bool first
                true  if this is the first call (for "tag" and "description"), and
                the first character of the value should be highlighted.

           int selected
                nonzero if the text  should  be  displayed  using  the  "selected"
                colors

### dlg_print_nowrap

           Print  the  line  within  the  given width, without wrapping.  Fill the
           remainder of the width with spaces.

           WINDOW *win
                the window in which to display the text

           const char *lin
                the value to display

           int width
                the number of columns available for printing the text, including a
                margin.

### dlg_print_scrolled

           This  is  a  wrapper  for  dlg_print_autowrap  which allows the user to
           scroll too-long prompt text up/down.

           See dlg_check_scrolled for a function which updates the offset variable
           used as a parameter here.  It complements this function; you need both.
           If pauseopt is set, this function returns an  updated  last  parameter,
           needed for dlg_check_scrolled calls.

           WINDOW * win
                is the window to update.

           const char * prompt
                is the string to print

           int offset
                is the starting line-number to write wrapped text.

           int height
                is the available height for writing the wrapped text

           int width
                is the width that the wrapping should occur in

           int pauseopt
                is  true  if  the  extra  functionality  for  scrolling  should be
                enabled.  If false, this calls  dlg_print_autowrap  without  doing
                any scrolling.

### dlg_prev_ok_buttonindex

           Find the previous button index in the list from dlg_ok_labels.

           int current
                is the current index

           int extra
                if  negative provides a way to enumerate extra active areas on the
                widget.

### dlg_print_autowrap

           Print a string of text in a window, automatically wrap  around  to  the
           next  line if the string is too long to fit on one line.  Note that the
           string may contain embedded newlines.  The text is written starting  at
           the top of the window.

           WINDOW * win
                is the window to update.

           const char * prompt
                is the string to print

           int height
                is the nominal height the wrapped string is limited to

           int width
                is the width that the wrapping should occur in

### dlg_print_size

           If  dialog_vars.print_siz is true, print the given height/width (from a
           widget) to dialog_state.output, e.g., Size: height, width.

           int height
                is the window's height

           int width
                is the window's width

### dlg_print_text

           Print up to cols  columns  from  text,  optionally  rendering  dialog's
           escape sequences for attributes and color.

           WINDOW * win
                is the window to update.

           const char * txt
                is the string to print

           int col
                is the column limit

           chtype * attr
                holds the starting attributes, and is updated to reflect the final
                attributes applied to the string.

### dlg_progressbox

           implements the "--prgbox" and "--progressbox" options.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.  If empty or null,  no
                prompt is shown.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

           int pauseopt
                if  true,  an  "OK" button will be shown, and the dialog will wait
                for it to  complete.   With  an  "OK"  button,  it  is  denoted  a
                "programbox",   without   an   "OK"   button,   it  is  denoted  a
                "progressbox".

           FILE * fp
                is the file pointer, which may be a pipe or a regular file.

### dlg_put_backtitle

           Display the background title if dialog_vars.backtitle is non-null.  The
           background title is shown at the top of the screen.

### dlg_reallocate_gauge

           Allocates  or reallocates a gauge widget (see dlg_allocate_gauge).  Use
           dlg_update_gauge to display the result.

           void ** objptr
                If the pointer referenced by this parameter is null, the  function
                creates  a  new gauge widget using dlg_allocate_gauge.  Otherwise,
                it updates the title and cprompt values, reusing the  window  from
                the  previous  call  on  this  function.   As  a  side-effect, the
                function  stores  the  updated  object-pointer  via   the   objptr
                parameter.

           const char * title
                is the title string to display at the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is adjusted
                to use the available screen size.

           int width
                is the desired width of the box.  If zero, the height is  adjusted
                to use the available screen size.

           int percent
                is the percentage to show in the progress bar.

### dlg_register_buttons

           The    widget    developer    should    call    this   function   after
           dlg_register_window, for the list of button labels associated with  the
           widget.  One may bind a key to a button, e.g., "OK" for DLGK_OK,

           WINDOW * win
                is the window with which to associate the buttons

           const char * name
                is the widget's binding name (usually the name of the widget).

           const char ** buttons
                is the list of buttons

### dlg_register_window

           For a given named widget's window, associate a binding table.

           WINDOW * win
                is the window with which to associate the buttons

           const char * name
                is the widget's binding name (usually the name of the widget).

           DLG_KEYS_BINDING * binding
                is the binding table

### dlg_remove_callback

           Remove a callback.

           DIALOG_CALLBACK * p
                contains the callback information.

### dlg_renamed_menutext

           This is a utility function which supports the --inputmenu option of the
           dialog program.  If dialog_vars.input_menu is set,  dialog_menu  passes
           this  pointer to dlg_menu as the rename_menutext parameter.  Otherwise,
           it passes dlg_dummy_menutext.

           The  function  should  add  "RENAMED"  to  dialog_vars.input_result   ,
           followed  by  the  menu item's name and the newtext value (with a space
           separating the three items), and return DLG_EXIT_EXTRA.

           DIALOG_LISTITEM * items
                is the list of menu items

           int current
                is the index of the currently-selected item

           char * newtext
                is the updated text for the menu item

### dlg_reset_timeout

           Calls wtimeout with the value saved for a window in the  last  call  to
           dlg_set_timeout.

### dlg_restore_vars

           Restore    dialog's    variables   from   the   given   variable   (see
           dialog_save_vars).

           DIALOG_VARS * save
                is the variable from which to restore.

           The DIALOG_VARS.input_length and DIALOG_VARS.input_result  members  are
           treated specially, since these are used by a widget to pass data to the
           caller.  They are not modified by this function.

### dlg_result_key

           Test a dialog internal keycode to see if it corresponds to one  of  the
           push  buttons on the widget such as "OK".  This is only useful if there
           are user-defined key bindings, since there  are  no  built-in  bindings
           that map directly to DLGK_OK, etc.  Return true if a mapping was done.

           int dialog_key
                is the dialog key to test

           int fkey
                is true if this is a function key

           int * resultp
                store the result of the mapping in the referenced location.

### dlg_save_vars

           Save dialog's variables into the given variable (see dlg_restore_vars).

           DIALOG_VARS * save
                is the variable into which to save.

### dlg_set_focus

           Set focus on the given window, making it display above other windows on
           the screen.

           WINDOW * parent
                is the parent window (usually the top-level window of a widget)

           WINDOW * win
                is the window on which to place focus (usually a  subwindow  of  a
                widget)

### dlg_set_result

           Setup a fixed-buffer for the result in dialog_vars.input_result

           const char * string
                is the new contents for the result

### dlg_set_timeout

           Calls  wtimeout to establish a preferred timeout for nonblocking reads,
           e.g., to allow the gauge widget to handle window-resizing events.   The
           dlg_may_resize  function  temporarily overrides this value, to allow it
           to skip over  the  error  codes  returned  while  the  ncurses  library
           processes window-resizing events.  It restores the value established in
           this call by calling dlg_restore_timeout.

           WINDOW * win
                is the window whose input-timeout should be set

           bool will_getc
                is true if the widget is expected  to  read  keyboard  characters.
                Some (such as the gauge widget) do not.

### dlg_show_string

           Displays  the  string,  shifted as necessary, to fit within the box and
           show the current character-offset.

           WINDOW * win
                is the window within which to display

           const char * string
                is the string to display

           int offset
                is the starting (character, not bytes) offset

           chtype attr
                is the window attribute to use for the string

           int y_base
                beginning row on screen

           int x_base
                beginning column on screen

           int x_last
                number of columns on screen

           bool hidden
                if true, do not echo input

           bool force
                if true, force repaint

### dlg_strclone

           duplicate the string, like strdup.

           const char * cprompt
                is the string to duplicate

### dlg_strcmp

           compare two strings, ignoring case.

           const char * a
                is one string

           const char * b
                is the other string

### dlg_string_to_argv

           Convert a string to an argument vector returning an index  (which  must
           be freed by the caller).  The string is modified:

           o   Blanks between arguments are replaced by nulls.

           o   Normally arguments are separated by blanks; however you can double-
               quote an argument to enclose blanks.  The surrounding double-quotes
               are removed from the string.

           o   A  backslash  preceding  a  double-quote  within  double-quotes  is
               removed.

           o   A backslash preceding a newline outside double-quotes is removed.

           o   Except for special cases, backslashes are preserved in the strings,
               since  other  dialog  functions  interpret  backslashes,  e.g., for
               colors.

           char *blob
                is the string to convert.

### dlg_sub_window

           create a subwindow, e.g., for an input area of a widget

           WINDOW * win
                is the parent window

           int height
                is the subwindow's height

           int width
                is the subwindow's width

           int y
                is the subwindow's top-row

           int x
                is the subwindow's left-column

### dlg_tab_correct_str

           If the dialog_vars.tab_correct is true, convert tabs to single  spaces.
           Return the converted result.  The caller is responsible for freeing the
           string.

           char * prompt
                is the string to convert

### dlg_trace

           If the parameter is non-null, opens a trace file  with  that  name  and
           stores the file pointer in dialog_state.trace.

### dlg_trace_2n

           logs a numeric value as a comment.

           char * name
                is the name to log in the comment.

           int value
                is the value to log in the comment.

### dlg_trace_2s

           logs  a  string  value  as  a  comment.  If the value contains embedded
           newlines, the comment is continued with "#+" markers.

           char * name
                is the name to log in the comment.

           int value
                is the value to log in the comment.

### dlg_trace_chr

           If dialog_state.trace is set, translate the parameters into a printable
           representation, log it on a "chr" line.

           int ch
                is the nominal keycode value.

           int fkey
                is  nonzero  if the value is really a function key.  Some of these
                may be values declared in the DLG_KEYS_ENUM.

### dlg_trace_msg

           Write a formatted message to the trace file.

           const char * fmt
                is the format of the printf-like message to write.

           ...
                are the variables to apply to the fmt format.

           Use the DLG_TRACE macro for portability, in case the trace  feature  is
           not  compiled  into the library.  It uses an extra level of parentheses
           to work with a variable number of parameters, e.g.,

                  DLG_TRACE(("this is dialog version %s\n", dialog_version()));

### dlg_trace_va_msg

           Write a formatted message to the trace file.

           const char *fmt
                is the format of the printf-like message to write.

           va_list ap
                are the variables to apply to the fmt format.

           This is used in dlg_exiterr to capture  error  messages  in  the  trace
           file:

                  va_start(ap, fmt);
                  dlg_trace_msg("## Error: ");
                  dlg_trace_va_msg(fmt, ap);
                  va_end(ap);

           Unlike dlg_trace_msg, an extra macro is not needed.

### dlg_ttysize

           Returns  the screensize without using curses.  That allows the function
           to be used before initializing the screen.

### dlg_trace_win

           If dialog_state.trace is set, log a  printable  picture  of  the  given
           window.

### dlg_treeview

           This   is  an  alternate  interface  to  'treeview'  which  allows  the
           application to read the list item states back directly without  putting
           them in the output buffer.

           const char * title
                is the title on the top of the widget.

           const char * cprompt
                is the prompt text shown within the widget.

           int height
                is the desired height of the box.  If zero, the height is based on
                the screen size.

           int width
                is the desired width of the box.  If zero, the height is based  on
                the screen size.

           int list_height
                is  the  minimum  height  to  reserve for displaying the list.  If
                zero, it is computed based on the given height and width.

           int item_no
                is the number of rows in items.

           DIALOG_LISTITEM * items
                is the list of items,  contain  tag,  name,  and  optionally  help
                strings  (if dialog_vars.item_help is set).  The initial selection
                state for each item is also in this list.

           const char * states
                This is a list of characters to  display  for  the  given  states.
                Normally a buildlist provides true (1) and false (0) values, which
                the  widget  displays  as  "*"  and   space,   respectively.    An
                application may set this parameter to an arbitrary null-terminated
                string.  The widget determines  the  number  of  states  from  the
                length  of  this  string, and will cycle through the corresponding
                display characters as the user presses the space-bar.

           int * depths
                This is a list of depths of each  item  in  the  tree.   It  is  a
                separate  parameter  from  items  to  allow  reuse of the existing
                functions.

           int flag
                is either FLAG_CHECK, for  checklists  (multiple  selections),  or
                FLAG_RADIO for radiolists (a single selection).

           int * current_item
                The  widget  sets  the  referenced  location  to  the index of the
                current display item (cursor) when it returns.

### dlg_trim_string

           The dialog program uses this in  each  widget  to  adjust  the  message
           string,  which  may contain the newline character (referred to as '\n')
           and/or the special substring "\n"  (which  can  be  translated  into  a
           newline character).

           There are several optional features:

           o   Unless  dialog_vars.nocollapse  is  set, each tab is converted to a
               space before other processing.

           o   If dialog_vars.no_nl_expand is not set, and  the  string  has  "\n"
               substrings:

               o   The   function   changes   embedded  "\n"  substrings  to  '\n'
                   characters.

                   The function preserves extra spaces after these  substitutions.
                   For   instance,   spaces  following  a  newline  (substring  or
                   character) are preserved to use as an indentation.

               o   If dialog_vars.cr_wrap is  set,  the  function  preserves  '\n'
                   newline  characters.  Otherwise, each '\n' newline character is
                   converted to a space.

           o   Otherwise, if dialog_vars.trim_whitespace is set:

               o   This   function   strips   all   extra   spaces   to   simplify
                   justification.

               o   If  dialog_vars.cr_wrap  is  set,  the  function preserves '\n'
                   newline characters.  Otherwise, each '\n' newline character  is
                   converted to a space.

           o   Finally (if dialog_vars.no_nl_expand is set, or the string does not
               contain "\n" substrings,  and  dialog_vars.trim_whitespace  is  not
               set):

               o   Unless  dialog_vars.nocollapse  is set, sequences of spaces are
                   reduced to a single space.

           char * src
                is the string to trim

### dlg_unregister_window

           Remove the bindings for a given window.

           WINDOW * win
                is the window from which to remove bindings

### dlg_update_gauge

           Update a gauge widget to show a different percentage value.

           void *objptr
                points to the gauge object to update.

           int percent
                is the new percentage value to display.

### dlg_will_resize

           This filters out bursts of KEY_RESIZE values.  Call this after dlg_getc
           returns KEY_RESIZE, to improve performance.

### dlg_yes_buttoncode

           Map the given button index for dlg_yes_labels into dialog's exit-code.

           int button
                is the button index

### dlg_yes_labels

           Return a list of buttons for Yes/No labels.

### end_dialog

           End use of dialog functions.

### init_dialog

           Do some initialization for dialog.

           FILE *input
                is  the  real  tty  input  of  dialog.  Usually it is the standard
                input, but if --input-fd option is used, it may be anything.

           FILE *output
                is where dialog will send its result.  Usually it is the  standard
                error, but if --stdout or --output-fd is used, it may be anything.

## AUTHORS

           Thomas E. Dickey

## SEE ALSO

           dialog(1).

                                      2024-01-01                          DIALOG()