'\" 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.

.SH NAME

tecla, teclarc \- User interface provided by the tecla library.

.SH DESCRIPTION

.sp

.LP

This man page describes the command-line editing features that are available to users of programs that read keyboard input via the tecla library. Users of the \fBtcsh shell\fR will find the default key bindings very familiar. Users of the \fBbash\fR shell will also find it quite familiar, but with a few minor differences, most notably in how forward and backward searches through the list of historical commands are performed. There are two major editing modes, one with \fBemacs\fR-like key bindings and another with \fBvi\fR-like key bindings. By default \fBemacs\fR mode is enabled, but \fBvi\fR(1) mode can alternatively be selected via the user's configuration file. This file can also be used to change the bindings of individual keys to suit the user's preferences. By default, tab completion is provided. If the application hasn't reconfigured this to complete other types of symbols, then tab completion completes file names.

.SS "Key Sequence Notation"

.sp

.LP

In the rest of this man page, and also in all tecla configuration files, key sequences are expressed as follows.

.sp

.ne 2

.mk

.na

\fB\fB^A\fR or \fBC-a\fR\fR

.ad

.RS 13n

.rt  

This is a 'CONTROL-A', entered by pressing the CONTROL key at the same time as the 'A' key.

.RE

.sp

.ne 2

.mk

.na

\fB\fB\eE\fR or \fBM-\fR\fR

.ad

.RS 13n

.rt  

In key sequences, both of these notations can be entered either by pressing the ESCAPE key, then the following key, or by pressing the META key at the same time as the following key. Thus the key sequence \fBM-p\fR can be typed in two ways, by pressing the ESCAPE key, followed by pressing 'P', or by pressing the META key at the same time as 'P'.

.RE

.sp

.ne 2

.mk

.na

\fBup\fR

.ad

.RS 13n

.rt  

This refers to the up-arrow key.

.RE

.sp

.ne 2

.mk

.na

\fBdown\fR

.ad

.RS 13n

.rt  

This refers to the down-arrow key.

.RE

.sp

.ne 2

.mk

.na

\fBleft\fR

.ad

.RS 13n

.rt  

This refers to the left-arrow key.

.RE

.sp

.ne 2

.mk

.na

\fBright\fR

.ad

.RS 13n

.rt  

This refers to the right-arrow key.

.RE

.sp

.ne 2

.mk

.na

\fBa\fR

.ad

.RS 13n

.rt  

This is just a normal 'A' key.

.RE

.SS "The Tecla Configuration File"

.sp

.LP

By default, tecla looks for a file called \fB\&.teclarc\fR in your home directory (ie. \fB~/.teclarc\fR). If it finds this file, it reads it, interpreting each line as defining a new key binding or an editing configuration option. Since the \fBemacs\fR key-bindings are installed by default, if you want to use the non-default \fBvi\fR editing mode, the most important item to go in this file is the following line:

.sp

.in +2

.nf

edit-mode vi

.fi

.in -2

.sp

.LP

This will re-configure the default bindings for \fBvi\fR-mode. The complete set of arguments that this command accepts are:

.sp

.ne 2

.mk

.na

\fBvi\fR

.ad

.RS 9n

.rt  

Install key bindings like those of the \fBvi\fR editor.

.RE

.sp

.ne 2

.mk

.na

\fBemacs\fR

.ad

.RS 9n

.rt  

Install key bindings like those of the \fBemacs\fR editor. This is the default.

.RE

.sp

.ne 2

.mk

.na

\fBnone\fR

.ad

.RS 9n

.rt  

Use just the native line editing facilities provided by the terminal driver.

.RE

.sp

.LP

To prevent the terminal bell from being rung, such as when an unrecognized control-sequence is typed, place the following line in the configuration file:

.sp

.in +2

.nf

nobeep

.fi

.in -2

.sp

.LP

An example of a key binding line in the configuration file is the following.

.sp

.in +2

.nf

bind M-[2~ insert-mode

.fi

.in -2

.sp

.LP

On many keyboards, the above key sequence is generated when one presses the insert key, so with this key binding, one can toggle between the \fBemacs\fR-mode insert and overwrite modes by hitting one key. One could also do it by typing out the above sequence of characters one by one. As explained above, the \fBM-\fR part of this sequence can be typed either by pressing the ESCAPE key before the following key, or by pressing the META key at the same time as the following key. Thus if you had set the above key binding, and the insert key on your keyboard didn't generate the above key sequence, you could still type it in either of the following 2 ways.

.RS +4

.TP

1.

Hit the ESCAPE key momentarily, then press '[', then \&'2', then finally '~'.

.RE

.RS +4

.TP

2.

Press the META key at the same time as pressing the \&'[' key, then press '2', then '~'.

.RE

.sp

.LP

If you set a key binding for a key sequence that is already bound to a function, the new binding overrides the old one. If in the new binding you omit the name of the new function to bind to the key sequence, the original binding becomes undefined.

.sp

.LP

Starting with versions of \fBlibtecla\fR later than 1.3.3 it is now possible to bind key sequences that begin with a printable character. Previously key sequences were required to start with a CONTROL or META character.

.sp

.LP

Note that the special keywords "up", "down", "left", and "right" refer to the arrow keys, and are thus not treated as key sequences. So, for example, to rebind the up and down arrow keys to use the history search mechanism instead of the simple history recall method, you could place the following in your configuration file:

.sp

.in +2

.nf

bind up history-search-backwards

bind down history-search-backwards

.fi

.in -2

.sp

.LP

To unbind an existing binding, you can do this with the bind command by omitting to name any action to rebind the key sequence to. For example, by not specifying an action function, the following command unbinds the default beginning-of-line action from the \fB^A\fR key sequence:

.sp

.in +2

.nf

bind ^A

.fi

.in -2

.sp

.LP

If you create a \fB~/.teclarc\fR configuration file, but it appears to have no effect on the program, check the documentation of the program to see if the author chose a different name for this file.

.SS "Filename and Tilde Completion"

.sp

.LP

With the default key bindings, pressing the TAB key (aka. \fB^I\fR) results in tecla attempting to complete the incomplete file name that precedes the cursor. Tecla searches backwards from the cursor, looking for the start of the file name, stopping when it hits either a space or the start of the line. If more than one file has the specified prefix, then tecla completes the file name up to the point at which the ambiguous matches start to differ, then lists the possible matches.

.sp

.LP

In addition to literally written file names, tecla can complete files that start with \fB~/\fR and \fB~user/\fR expressions and that contain \fB$envvar\fR expressions. In particular, if you hit TAB within an incomplete \fB~user\fR, expression, tecla will attempt to complete the username, listing any ambiguous matches.

.sp

.LP

The completion binding is implemented using the \fBcpl_complete_word()\fR function, which is also available separately to users of this library. See the \fBcpl_complete_word\fR(3TECLA) man page for more details.

.SS "Filename Expansion"

.sp

.LP

With the default key bindings, pressing \fB^X*\fR causes tecla to expand the file name that precedes the cursor, replacing \fB~/\fR and \fB~user/\fR expressions with the corresponding home directories, and replacing \fB$envvar\fR expressions with the value of the specified environment variable, then if there are any wildcards, replacing the so far expanded file name with a space-separated list of the files which match the wild cards.

.sp

.LP

The expansion binding is implemented using the \fBef_expand_file()\fR function. See the \fBef_expand_file\fR(3TECLA) man page for more details.

.SS "Recalling Previously Typed Lines"

.sp

.LP

Every time that a new line is entered by the user, it is appended to a list of historical input lines maintained within the \fBGetLine\fR resource object. You can traverse up and down this list using the up and down arrow keys. Alternatively, you can do the same with the \fB^P\fR, and \fB^N\fR keys, and in \fBvi\fR command mode you can alternatively use the k and j characters. Thus pressing up-arrow once, replaces the current input line with the previously entered line. Pressing up-arrow again, replaces this with the line that was entered before it, etc.. Having gone back one or more lines into the history list, one can return to newer lines by pressing down-arrow one or more times. If you do this sufficient times, you will return to the original line that you were entering when you first hit up-arrow.

.sp

.LP

Note that in \fBvi\fR mode, all of the history recall functions switch the library into command mode.

.sp

.LP

In \fBemacs\fR mode the \fBM-p\fR and \fBM-n\fR keys work just like the \fB^P\fR and \fB^N\fR keys, except that they skip all but those historical lines which share the prefix that precedes the cursor. In \fBvi\fR command mode the upper case 'K' and 'J' characters do the same thing, except that the string that they search for includes the character under the cursor as well as what precedes it.

.sp

.LP

Thus for example, suppose that you were in \fBemacs\fR mode, and you had just entered the following list of commands in the order shown:

.sp

.in +2

.nf

ls ~/tecla/

cd ~/tecla

ls -l getline.c

\fBemacs\fR ~/tecla/getline.c

.fi

.in -2

.sp

.LP

If you next typed:

.sp

.in +2

.nf

ls

.fi

.in -2

.sp

.LP

and then hit \fBM-p\fR, then rather than returning the previously typed \fBemacs\fR line, which doesn't start with "ls", tecla would recall the "ls -l getline.c" line. Pressing \fBM-p\fR again would recall the "ls ~/tecla/" line.

.sp

.LP

.sp

.in +2

.nf

*tecla*

.fi

.in -2

.sp

.LP

and hit \fBM-p\fR, then the "\fBemacs\fR ~/tecla/getline.c" line would be recalled first, since it contains the word tecla somewhere in the line, Similarly, hitting \fBM-p\fR again, would recall the "ls ~/tecla/" line, and hitting it once more would recall the "ls ~/tecla/" line. The pattern syntax is the same as that described for file name expansion, in the \fBef_expand_file\fR(3TECLA).

.SS "History Files"

.sp

.LP

Authors of programs that use the tecla library have the option of saving historical command-lines in a file before exiting, and subsequently reading them back in from this file when the program is next started. There is no standard name for this file, since it makes sense for each application to use its own history file, so that commands from different applications don't get mixed up.

.SS "International Character Sets"

.sp

.LP

Since \fBlibtecla\fR version 1.4.0, tecla has been 8-bit clean. This means that all 8-bit characters that are printable in the user's current locale are now displayed verbatim and included in the returned input line. Assuming that the calling program correctly contains a call like the following,

.sp

.in +2

.nf

setlocale(LC_CTYPE, "");

.fi

.in -2

.sp

.LP

then the current locale is determined by the first of the environment variables \fBLC_CTYPE\fR, \fBLC_ALL\fR, and \fBLANG\fR, that is found to contain a valid locale name. If none of these variables are defined, or the program neglects to call \fBsetlocale\fR, then the default C locale is used, which is US 7-bit ASCII. On most unix-like platforms, you can get a list of valid locales by typing the command:

.sp

.in +2

.nf

locale -a

.fi

.in -2

.sp

.LP

at the shell prompt.

.SS "Meta Keys and Locales"

.sp

.LP

Beware that in most locales other than the default C locale, META characters become printable, and they are then no longer considered to match \fBM-c\fR style key bindings. This allows international characters to be entered with the compose key without unexpectedly triggering META key bindings. You can still invoke META bindings, since there are actually two ways to do this. For example the binding \fBM-c\fR can also be invoked by pressing the ESCAPE key momentarily, then pressing the c key, and this will work regardless of locale. Moreover, many modern terminal emulators, such as gnome's gnome-terminal's and KDE's konsole terminals, already generate escape pairs like this when you use the META key, rather than a real meta character, and other emulators usually have a way to request this behavior, so you can continue to use the META key on most systems.

.sp

.LP

For example, although xterm terminal emulators generate real 8-bit meta characters by default when you use the META key, they can be configured to output the equivalent escape pair by setting their \fBEightBitInput\fR X resource to False. You can either do this by placing a line like the following in your \fB~/.Xdefaults\fR file,

.sp

.in +2

.nf

XTerm*EightBitInput: False

.fi

.in -2

.sp

.LP

or by starting an \fBxterm\fR with an \fB-xrm\fR '*EightBitInput: False' command-line argument. In recent versions of xterm you can toggle this feature on and off with the 'Meta Sends Escape' option in the menu that is displayed when you press the left mouse button and the CONTROL key within an xterm window. In CDE, dtterms can be similarly coerced to generate escape pairs in place of meta characters, by setting the \fBDtterm*KshMode\fR resource to True.

.SS "Entering International Characters"

.sp

.LP

If you don't have a keyboard that generates all of the international characters that you need, there is usually a compose key that will allow you to enter special characters, or a way to create one. For example, under X windows on unix-like systems, if your keyboard doesn't have a compose key, you can designate a redundant key to serve this purpose with the xmodmap command. For example, on many PC keyboards there is a microsoft-windows key, which is otherwise useless under Linux. On a laptop, for example, the \fBxev\fR program might report that pressing this key generates keycode 115. To turn this key into a COMPOSE  key, do the following:

.sp

.in +2

.nf

xmodmap -e 'keycode 115 = Multi_key'

.fi

.in -2

.sp

.LP

Type this key followed by a " character to enter an 'I' with a umlaut over it.

.SS "The Available Key Binding Functions"

.sp

.LP

The following is a list of the editing functions provided by the tecla library. The names in the leftmost column of the list can be used in configuration files to specify which function a given key or combination of keys should invoke. They are also used in the next two sections to list the default key bindings in \fBemacs\fR and \fBvi\fR modes.

.sp

.ne 2

.mk

.na

\fBuser-interrupt\fR

.ad

.RS 30n

.rt  

Send a SIGINT signal to the parent process.

.RE

.sp

.ne 2

.mk

.na

\fBsuspend\fR

.ad

.RS 30n

.rt  

Suspend the parent process.

.RE

.sp

.ne 2

.mk

.na

\fBstop-output\fR

.ad

.RS 30n

.rt  

Pause terminal output.

.RE

.sp

.ne 2

.mk

.na

\fBstart-output\fR

.ad

.RS 30n

.rt  

Resume paused terminal output.

.RE

.sp

.ne 2

.mk

.na

\fBliteral-next\fR

.ad

.RS 30n

.rt  

Arrange for the next character to be treated as a normal character. This allows control characters to be entered.

.RE

.sp

.ne 2

.mk

.na

\fBcursor-right\fR

.ad

.RS 30n

.rt  

Move the cursor one character right.

.RE

.sp

.ne 2

.mk

.na

\fBcursor-left\fR

.ad

.RS 30n

.rt  

Move the cursor one character left.

.RE

.sp

.ne 2

.mk

.na

\fBinsert-mode\fR

.ad

.RS 30n

.rt  

Toggle between insert mode and overwrite mode.

.RE

.sp

.ne 2

.mk

.na

\fBbeginning-of-line\fR

.ad

.RS 30n

.rt  

Move the cursor to the beginning of the line.

.RE

.sp

.ne 2

.mk

.na

\fBend-of-line\fR

.ad

.RS 30n

.rt  

Move the cursor to the end of the line.

.RE

.sp

.ne 2

.mk

.na

\fBdelete-line\fR

.ad

.RS 30n

.rt  

Delete the contents of the current line.

.RE

.sp

.ne 2

.mk

.na

\fBkill-line\fR

.ad

.RS 30n

.rt  

Delete everything that follows the cursor.

.RE

.sp

.ne 2

.mk

.na

\fBbackward-kill-line\fR

.ad

.RS 30n

.rt  

Delete all characters between the cursor and the start of the line.

.RE

.sp

.ne 2

.mk

.na

\fBforward-word\fR

.ad

.RS 30n

.rt  

Move to the end of the word which follows the cursor.

.RE

.sp

.ne 2

.mk

.na

\fBforward-to-word\fR

.ad

.RS 30n

.rt  

Move the cursor to the start of the word that follows the cursor.

.RE

.sp

.ne 2

.mk

.na

\fBbackward-word\fR

.ad

.RS 30n

.rt  

Move to the start of the word which precedes the cursor.

.RE

.sp

.ne 2

.mk

.na

\fBgoto-column\fR

.ad

.RS 30n

.rt  

Move the cursor to the 1-relative column in the line specified by any preceding digit-argument sequences (see Entering Repeat Counts below).

.RE

.sp

.ne 2

.mk

.na

\fBfind-parenthesis\fR

.ad

.RS 30n

.rt  

If the cursor is currently over a parenthesis character, move it to the matching parenthesis character. If not over a parenthesis character move right to the next close parenthesis.

.RE