dialog(3)
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 setup 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. .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_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). .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. .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: 0
through 7 are the ANSI codes used in curses: black, red, green, yellow,
blue, magenta, cyan and white respectively. Bold is set by 'b', reset
by 'B'. Reverse is set by 'r', reset by 'R'. 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.
.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, make the
default button of widgets that provide "OK" and "Cancel" a Cancel. If
--nocancel 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.
.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.
.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. 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:
* 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>.
* 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:
* by default, the calendar treats January 1 as the first week of the
year.
* 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_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 "--nook. 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.
.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.
.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
* a number (0 to 6, Sunday through Saturday using POSIX) or
* the special value "locale" (this works with systems using glibc,
providing an extension to the locale command, the first_weekday
value).
* 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 setup 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.
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. 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 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.
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
Automatically size the window used for a widget. If the given height
or width are zero, justify the prompt text and return the actual
limits.
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.
int * height
is the nominal height.
int * width
is the nominal width.
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).
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).
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:
* if neither dialog_vars.ascii_lines nor dialog_vars.no_lines is set.
* if dialog_vars.ascii_lines is set, returns the corresponding "+" or
"-", etc. for the line-drawing characters used in dialog.
* otherwise, if dialog_vars.no_lines is set, returns a space for the
line-drawing characters.
* 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_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_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_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_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_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
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_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_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_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_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_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_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_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 (replacing gaps
between tokens with nulls).
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_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_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:
* Unless dialog_vars.no_nl_expand is set,
* If it has "\n" substrings, the function preserves extra spaces.
For instance, spaces following a newline (substring or character)
are preserved to use as an indentation.
* The function changes embedded "\n" substrings to '\n' characters.
* If dialog_vars.no_nl_expand is not set, or if there are no "\n"
substrings, this function strips all extra spaces to simplify
justification.
* If dialog_vars.cr_wrap is set, the function preserves '\n' newline
characters. Otherwise, each '\n' newline character is converted to
a space.
* Unless dialog_vars.nocollapse is set, each tab character is
converted to a space, and sequences of blanks (space or tab) 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_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.
SEE ALSO
dialog (1).
AUTHOR
Thomas E. Dickey $Date: 2016/08/27 13:08:15 $ DIALOG(3)
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