'\" te

.\" Copyright (c) 2000, 2001, 2002, 2003, 2004 by Martin C. Shepherd. All Rights Reserved.

.\" Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, provided that the above copyright notice(s) and this permission notice appear in all copies of the Software and that both the above copyright notice(s) and this permission notice appear in supporting documentation.  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  Except as contained in this notice, the name of a copyright holder shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization of the copyright holder.

.\" Portions Copyright (c) 2007, Sun Microsystems, Inc. All Rights Reserved.

.TH gl_get_line 3TECLA "28 Nov 2007" "SunOS 5.11" "Interactive Command-line Input Library Functions"

.SH NAME

gl_get_line, new_GetLine, del_GetLine, gl_customize_completion, gl_change_terminal, gl_configure_getline, gl_load_history, gl_save_history, gl_group_history, gl_show_history, gl_watch_fd, gl_inactivity_timeout, gl_terminal_size, gl_set_term_size, gl_resize_history, gl_limit_history, gl_clear_history, gl_toggle_history, gl_lookup_history, gl_state_of_history, gl_range_of_history, gl_size_of_history, gl_echo_mode, gl_replace_prompt, gl_prompt_style, gl_ignore_signal, gl_trap_signal, gl_last_signal, gl_completion_action, gl_register_action, gl_display_text, gl_return_status, gl_error_message, gl_catch_blocked, gl_list_signals, gl_bind_keyseq, gl_erase_terminal, gl_automatic_history, gl_append_history, gl_query_char, gl_read_char \- allow the user to compose an input line

.SH SYNOPSIS

.LP

.nf

cc [ \fIflag\fR\&.\|.\|. ] \fIfile\fR\&.\|.\|. \fB-ltecla\fR [ \fIlibrary\fR\&.\|.\|. ] 

#include <stdio.h>

#include <libtecla.h>

\fBGetLine *\fR\fBnew_GetLine\fR(\fBsize_t\fR \fIlinelen\fR, \fBsize_t\fR \fIhistlen\fR);

.fi

.LP

.nf

\fBGetLine *\fR\fBdel_GetLine\fR(\fBGetLine *\fR\fIgl\fR);

.fi

.LP

.nf

\fBchar *\fR\fBgl_get_line\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIprompt\fR,

     \fBconst char *\fR\fIstart_line\fR, \fBint\fR \fIstart_pos\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_query_char\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIprompt\fR, \fBchar\fR \fIdefchar\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_read_char\fR(\fBGetLine *\fR\fIgl\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_customize_completion\fR(\fBGetLine *\fR\fIgl\fR, \fBvoid *\fR\fIdata\fR,

     \fBCplMatchFn *\fR\fImatch_fn\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_change_terminal\fR(\fBGetLine *\fR\fIgl\fR, \fBFILE *\fR\fIinput_fp\fR,

     \fBFILE *\fR\fIoutput_fp\fR, \fBconst char *\fR\fIterm\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_configure_getline\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIapp_string\fR,

     \fBconst char *\fR\fIapp_file\fR,\ \fBconst char *\fR\fIuser_file\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_bind_keyseq\fR(\fBGetLine *\fR\fIgl\fR, \fBGlKeyOrigin\fR \fIorigin\fR,

     \fBconst char *\fR\fIkeyseq\fR, \fBconst char *\fR\fIaction\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_save_history\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIfilename\fR,

     \fBconst char *\fR\fIcomment\fR, \fBint\fR \fImax_lines\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_load_history\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIfilename\fR,

     \fBconst char *\fR\fIcomment\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_watch_fd\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIfd\fR, \fBGlFdEvent\fR \fIevent\fR,

     \fBGlFdEventFn *\fR\fIcallback\fR, \fBvoid *\fR\fIdata\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_inactivity_timeout\fR(\fBGetLine *\fR\fIgl\fR, \fBGlTimeoutFn *\fR\fIcallback\fR,

     \fBvoid *\fR\fIdata\fR, \fBunsigned long\fR \fIsec\fR, \fBunsigned long\fR \fInsec\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_group_history\fR(\fBGetLine *\fR\fIgl\fR, \fBunsigned\fR \fIstream\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_show_history\fR(\fBGetLine *\fR\fIgl\fR, \fBFILE *\fR\fIfp\fR, \fBconst char *\fR\fIfmt\fR,

     \fBint\fR \fIall_groups\fR, \fBint\fR \fImax_lines\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_resize_history\fR(\fBGetLine *\fR\fIgl\fR, \fBsize_t\fR \fIbufsize\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_limit_history\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fImax_lines\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_clear_history\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIall_groups\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_toggle_history\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIenable\fR);

.fi

.LP

.nf

\fBGlTerminalSize\fR \fBgl_terminal_size\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIdef_ncolumn\fR,

     \fBint\fR \fIdef_nline\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_set_term_size\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIncolumn\fR, \fBint\fR \fInline\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_lookup_history\fR(\fBGetLine *\fR\fIgl\fR, \fBunsigned long\fR \fIid\fR,

     \fBGlHistoryLine *\fR\fIhline\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_state_of_history\fR(\fBGetLine *\fR\fIgl\fR, \fBGlHistoryState *\fR\fIstate\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_range_of_history\fR(\fBGetLine *\fR\fIgl\fR, \fBGlHistoryRange *\fR\fIrange\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_size_of_history\fR(\fBGetLine *\fR\fIgl\fR, \fBGlHistorySize *\fR\fIsize\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_echo_mode\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIenable\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_replace_prompt\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIprompt\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_prompt_style\fR(\fBGetLine *\fR\fIgl\fR, \fBGlPromptStyle\fR \fIstyle\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_ignore_signal\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIsigno\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_trap_signal\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIsigno\fR, \fBunsigned\fR \fIflags\fR,

     \fBGlAfterSignal\fR \fIafter\fR, \fBint\fR \fIerrno_value\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_last_signal\fR(\fBGetLine *\fR\fIgl\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_completion_action\fR(\fBGetLine *\fR\fIgl\fR, \fBvoid *\fR\fIdata\fR,

     \fBCplMatchFn *\fR\fImatch_fn\fR, \fBint\fR \fIlist_only\fR, \fBconst char *\fR\fIname\fR,

     \fBconst char *\fR\fIkeyseq\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_register_action\fR(\fBGetLine *\fR\fIgl\fR, \fBvoid *\fR\fIdata\fR, \fBGlActionFn *\fR\fIfn\fR,

     \fBconst char *\fR\fIname\fR, \fBconst char *\fR\fIkeyseq\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_display_text\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIindentation\fR,

     \fBconst char *\fR\fIprefix\fR, \fBconst char *\fR\fIsuffix\fR, \fBint\fR \fIfill_char\fR,

     \fBint\fR \fIdef_width\fR, \fBint\fR \fIstart\fR, \fBconst char *\fR\fIstring\fR);

.fi

.LP

.nf

\fBGlReturnStatus\fR \fBgl_return_status\fR(\fBGetLine *\fR\fIgl\fR);

.fi

.LP

.nf

\fBconst char *\fR\fBgl_error_message\fR(\fBGetLine *\fR\fIgl\fR, \fBchar *\fR\fIbuff\fR, \fBsize_t\fR \fIn\fR);

.fi

.LP

.nf

\fBvoid\fR \fBgl_catch_blocked\fR(\fBGetLine *\fR\fIgl\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_list_signals\fR(\fBGetLine *\fR\fIgl\fR, \fBsigset_t *\fR\fIset\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_append_history\fR(\fBGetLine *\fR\fIgl\fR, \fBconst char *\fR\fIline\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_automatic_history\fR(\fBGetLine *\fR\fIgl\fR, \fBint\fR \fIenable\fR);

.fi

.LP

.nf

\fBint\fR \fBgl_erase_terminal\fR(\fBGetLine *\fR\fIgl\fR);

.fi

.SH DESCRIPTION

.sp

.LP

The \fBgl_get_line()\fR function is part of the \fBlibtecla\fR(3LIB) library. If the user is typing at a terminal, each call prompts them for an line of input, then provides interactive editing facilities, similar to those of the UNIX \fBtcsh\fR shell. In addition to simple command-line editing, it supports recall of previously entered command lines, TAB completion of file names, and in-line wild-card expansion of filenames. Documentation of both the user-level command-line editing features and all user configuration options can be found on the \fBtecla\fR(5) manual page.

.SS "An Example"

.sp

.LP

The following shows a complete example of how to use the \fBgl_get_line()\fR function to get input from the user:

.sp

.in +2

.nf

#include <stdio.h>

#include <locale.h>

#include <libtecla.h>

int main(int argc, char *argv[])

{

  char *line;    /* The line that the user typed */

  GetLine *gl;   /* The gl_get_line() resource object */

  setlocale(LC_CTYPE, ""); /* Adopt the user's choice */

                           /* of character set. */

  gl = new_GetLine(1024, 2048);

  if(!gl)

    return 1;

  while((line=gl_get_line(gl, "$ ", NULL, -1)) != NULL &&

         strcmp(line, "exit\en") != 0)

    printf("You typed: %s\en", line);

  gl = del_GetLine(gl);

  return 0;

}

.fi

.in -2

.sp

.LP

In the example, first the resources needed by the \fBgl_get_line()\fR function are created by calling \fBnew_GetLine()\fR. This allocates the memory used in subsequent calls to the \fBgl_get_line()\fR function, including the history buffer for recording previously entered lines. Then one or more lines are read from the user, until either an error occurs, or the user types exit. Then finally the resources that were allocated by \fBnew_GetLine()\fR, are returned to the system by calling \fBdel_GetLine()\fR. Note the use of the \fINULL\fR return value of \fBdel_GetLine()\fR to make \fIgl\fR \fINULL\fR. This is a safety precaution. If the program subsequently attempts to pass \fIgl\fR to \fBgl_get_line()\fR, said function will complain, and return an error, instead of attempting to use the deleted resource object.

.SS "The Functions Used In The Example"

.sp

.LP

The \fBnew_GetLine()\fR function creates the resources used by the \fBgl_get_line()\fR function and returns an opaque pointer to the object that contains them. The maximum length of an input line is specified by the \fIlinelen\fR argument, and the number of bytes to allocate for storing history lines is set by the \fIhistlen\fR argument. History lines are stored back-to-back in a single buffer of this size. Note that this means that the number of history lines that can be stored at any given time, depends on the lengths of the individual lines. If you want to place an upper limit on the number of lines that can be stored, see the description of the \fBgl_limit_history()\fR function. If you do not want history at all, specify \fIhistlen\fR as zero, and no history buffer will be allocated.

.sp

.LP

On error, a message is printed to \fBstderr\fR and \fINULL\fR is returned.

.sp

.LP

The \fBdel_GetLine()\fR function deletes the resources that were returned by a previous call to \fBnew_GetLine()\fR. It always returns \fINULL\fR (for example, a deleted object). It does nothing if the \fIgl\fR argument is \fINULL\fR.

.sp

.LP

The \fBgl_get_line()\fR function can be called any number of times to read input from the user. The gl argument must have been previously returned by a call to \fBnew_GetLine()\fR. The \fIprompt\fR argument should be a normal null-terminated string, specifying the prompt to present the user with. By default prompts are displayed literally, but if enabled with the \fBgl_prompt_style()\fR function, prompts can contain directives to do underlining, switch to and from bold fonts, or turn highlighting on and off.

.sp

.LP

If you want to specify the initial contents of the line for the user to edit, pass the desired string with the \fIstart_line\fR argument. You can then specify which character of this line the cursor is initially positioned over by using the \fIstart_pos\fR argument. This should be -1 if you want the cursor to follow the last character of the start line. If you do not want to preload the line in this manner, send \fIstart_line\fR as \fINULL\fR, and set \fIstart_pos\fR to -1.

.sp

.LP

The \fBgl_get_line()\fR function returns a pointer to the line entered by the user, or \fINULL\fR on error or at the end of the input. The returned pointer is part of the specified \fIgl\fR resource object, and thus should not be freed by the caller, or assumed to be unchanging from one call to the next. When reading from a user at a terminal, there will always be a newline character at the end of the returned line. When standard input is being taken from a pipe or a file, there will similarly be a newline unless the input line was too long to store in the internal buffer. In the latter case you should call \fBgl_get_line()\fR again to read the rest of the line. Note that this behavior makes \fBgl_get_line()\fR similar to \fBfgets\fR(3C). When \fBstdin\fR is not connected to a terminal, \fBgl_get_line()\fR simply calls \fBfgets()\fR.

.SS "The Return Status Of \fBgl_get_line()\fR"

.sp

.LP

The \fBgl_get_line()\fR function has two possible return values: a pointer to the completed input line, or \fINULL\fR. Additional information about what caused \fBgl_get_line()\fR to return is available both by inspecting \fBerrno\fR and by calling the \fBgl_return_status()\fR function.

.sp

.LP

The following are the possible enumerated values returned by \fBgl_return_status()\fR:

.sp

.ne 2

.mk

.na

\fB\fBGLR_NEWLINE\fR\fR

.ad

.RS 15n

.rt  

The last call to \fBgl_get_line()\fR successfully returned a completed input line.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGLR_BLOCKED\fR\fR

.ad

.RS 15n

.rt  

The \fBgl_get_line()\fR function was in non-blocking server mode, and returned early to avoid blocking the process while waiting for terminal I/O. The \fBgl_pending_io()\fR function can be used to see what type of I/O \fBgl_get_line()\fR was waiting for. See the \fBgl_io_mode\fR(3TECLA).

.RE

.sp

.ne 2

.mk

.na

\fB\fBGLR_SIGNAL\fR\fR

.ad

.RS 15n

.rt  

A signal was caught by \fBgl_get_line()\fR that had an after-signal disposition of \fBGLS_ABORT\fR. See \fBgl_trap_signal()\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGLR_TIMEOUT\fR\fR

.ad

.RS 15n

.rt  

The inactivity timer expired while \fBgl_get_line()\fR was waiting for input, and the timeout callback function returned \fBGLTO_ABORT\fR. See \fBgl_inactivity_timeout()\fR for information about timeouts.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGLR_FDABORT\fR\fR

.ad

.RS 15n

.rt  

An application I/O callback returned \fBGLFD_ABORT\fR. Ssee \fBgl_watch_fd()\fR.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGLR_EOF\fR\fR

.ad

.RS 15n

.rt  

End of file reached. This can happen when input is coming from a file or a pipe, instead of the terminal. It also occurs if the user invokes the list-or-eof or del-char-or-list-or-eof actions at the start of a new line.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGLR_ERROR\fR\fR

.ad

.RS 15n

.rt  

An unexpected error caused \fBgl_get_line()\fR to abort (consult \fBerrno\fR and/or \fBgl_error_message()\fR for details.

.RE

.sp

.LP

When \fBgl_return_status()\fR returns \fBGLR_ERROR\fR and the value of \fBerrno\fR is not sufficient to explain what happened, you can use the \fBgl_error_message()\fR function to request a description of the last error that occurred.

.sp

.LP

The return value of \fBgl_error_message()\fR is a pointer to the message that occurred. If the \fIbuff\fR argument is \fINULL\fR, this will be a pointer to a buffer within \fIgl\fR whose value will probably change on the next call to any function associated with \fBgl_get_line()\fR. Otherwise, if a non-null \fIbuff\fR argument is provided, the error message, including a '\e0' terminator, will be written within the first \fIn\fR elements of this buffer, and the return value will be a pointer to the first element of this buffer. If the message will not fit in the provided buffer, it will be truncated to fit.

.SS "Optional Prompt Formatting"

.sp

.LP

Whereas by default the prompt string that you specify is displayed literally without any special interpretation of the characters within it, the \fBgl_prompt_style()\fR function can be used to enable optional formatting directives within the prompt.

.sp

.LP

The \fIstyle\fR argument, which specifies the formatting style, can take any of the following values:

.sp

.ne 2

.mk

.na

\fB\fBGL_FORMAT_PROMPT\fR\fR

.ad

.RS 21n

.rt  

In this style, the formatting directives described below, when included in prompt strings, are interpreted as follows:

.sp

.ne 2

.mk

.na

\fB\fB%B\fR\fR

.ad

.RS 6n

.rt  

Display subsequent characters with a bold font.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%b\fR\fR

.ad

.RS 6n

.rt  

Stop displaying characters with the bold font.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%F\fR\fR

.ad

.RS 6n

.rt  

Make subsequent characters flash.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%f\fR\fR

.ad

.RS 6n

.rt  

Turn off flashing characters.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%U\fR\fR

.ad

.RS 6n

.rt  

Underline subsequent characters.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%u\fR\fR

.ad

.RS 6n

.rt  

Stop underlining characters.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%P\fR\fR

.ad

.RS 6n

.rt  

Switch to a pale (half brightness) font.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%p\fR\fR

.ad

.RS 6n

.rt  

Stop using the pale font.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%S\fR\fR

.ad

.RS 6n

.rt  

Highlight subsequent characters (also known as standout mode).

.RE

.sp

.ne 2

.mk

.na

\fB\fB%s\fR\fR

.ad

.RS 6n

.rt  

Stop highlighting characters.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%V\fR\fR

.ad

.RS 6n

.rt  

Turn on reverse video.

.RE

.sp

.ne 2

.mk

.na

\fB\fB%v\fR\fR

.ad

.RS 6n

.rt  

Turn off reverse video.