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diff --git a/libtecla-1.4.1/man3/gl_get_line.3 b/libtecla-1.4.1/man3/gl_get_line.3 deleted file mode 100644 index 51fc9d8..0000000 --- a/libtecla-1.4.1/man3/gl_get_line.3 +++ /dev/null @@ -1,2329 +0,0 @@ -.\" Copyright (C) 2000, 2001 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. -.TH gl_get_line 3 -.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_terminal_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 \- allow the user to compose an input line -.SH SYNOPSIS -.nf -#include <stdio.h> -#include <libtecla.h> - -GetLine *new_GetLine(size_t linelen, size_t histlen); - -GetLine *del_GetLine(GetLine *gl); - -char *gl_get_line(GetLine *gl, const char *prompt, - const char *start_line, int start_pos); - -int gl_customize_completion(GetLine *gl, void *data, - CplMatchFn *match_fn); - -int gl_change_terminal(GetLine *gl, FILE *input_fp, - FILE *output_fp, const char *term); - -int gl_configure_getline(GetLine *gl, - const char *app_string, - const char *app_file, - const char *user_file); - -int gl_save_history(GetLine *gl, const char *filename, - const char *comment, int max_lines); - -int gl_load_history(GetLine *gl, const char *filename, - const char *comment); - -int gl_watch_fd(GetLine *gl, int fd, GlFdEvent event, - GlFdEventFn *callback, void *data); - -int gl_group_history(GetLine *gl, unsigned stream); - -int gl_show_history(GetLine *gl, FILE *fp, - const char *fmt, int all_groups, - int max_lines); - -int gl_resize_history(GetLine *gl, size_t bufsize); - -void gl_limit_history(GetLine *gl, int max_lines); - -void gl_clear_history(GetLine *gl, int all_groups); - -void gl_toggle_history(GetLine *gl, int enable); - -GlTerminalSize gl_terminal_size(GetLine *gl, - int def_ncolumn, - int def_nline); - -int gl_lookup_history(GetLine *gl, unsigned long id, - GlHistoryLine *hline); - -void gl_state_of_history(GetLine *gl, - GlHistoryState *state); - -void gl_range_of_history(GetLine *gl, - GlHistoryRange *range); - -void gl_size_of_history(GetLine *gl, GlHistorySize *size); - -void gl_echo_mode(GetLine *gl, int enable); - -void gl_replace_prompt(GetLine *gl, const char *prompt); - -void gl_prompt_style(GetLine *gl, GlPromptStyle style); - -int gl_ignore_signal(GetLine *gl, int signo); - -int gl_trap_signal(GetLine *gl, int signo, unsigned flags, - GlAfterSignal after, int errno_value); - -int gl_last_signal(const GetLine *gl); - -.fi - -.SH DESCRIPTION - -The \f3gl_get_line()\f1 function is part of the tecla library (see -the libtecla(3) man page). If the user is typing at a terminal, it -prompts them for an line of input, then provides interactive editing -facilities, similar to those of the unix \f3tcsh\f1 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. -.sp -.SH AN EXAMPLE - -The following shows a complete example of how to use the -\f3gl_get_line()\f1 function to get input from the user: - -.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\\n") != 0) - printf("You typed: %s\\n", line); - - gl = del_GetLine(gl); - return 0; - } -.fi -.sp -In the example, first the resources needed by the \f3gl_get_line()\f1 function -are created by calling \f3new_GetLine()\f1. This allocates the memory used in -subsequent calls to the \f3gl_get_line()\f1 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 \f3exit\f1. Then -finally the resources that were allocated by \f3new_GetLine()\f1, are returned -to the system by calling \f3del_GetLine()\f1. Note the use of the \f3NULL\f1 -return value of \f3del_GetLine()\f1 to make \f3gl\f1 \f3NULL\f1. This is a -safety precaution. If the program subsequently attempts to pass \f3gl\f1 to -\f3gl_get_line()\f1, said function will complain, and return an error, instead of -attempting to use the deleted resource object. - -.sp -.SH THE FUNCTIONS USED IN THE EXAMPLE -The descriptions of the functions used in the example are as follows: -.sp -.nf - GetLine *new_GetLine(size_t linelen, size_t histlen) -.fi -.sp -This function creates the resources used by the \f3gl_get_line()\f1 -function and returns an opaque pointer to the object that contains -them. The maximum length of an input line is specified via the -\f3linelen\f1 argument, and the number of bytes to allocate for -storing history lines is set by the \f3histlen\f1 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 \f3gl_limit_history()\f1 function described later. If -you don't want history at all, specify \f3histlen\f1 as zero, and no -history buffer will be allocated. -.sp -On error, a message is printed to \f3stderr\f1 and \f3NULL\f1 is returned. -.sp -.nf - GetLine *del_GetLine(GetLine *gl) -.fi -.sp -This function deletes the resources that were returned by a previous -call to \f3new_GetLine()\f1. It always returns \f3NULL\f1 (ie a -deleted object). It does nothing if the \f3gl\f1 argument is -\f3NULL\f1. -.sp -.nf - char *gl_get_line(GetLine *gl, const char *prompt, - const char *start_line, int start_pos); -.fi -.sp -The \f3gl_get_line()\f1 function can be called any number of -times to read input from the user. The \f3gl\f1 argument -must have been previously returned by a call to -\f3new_GetLine()\f1. The \f3prompt\f1 argument should be a -normal \f3NUL\f1 terminated string, specifying the prompt to -present the user with. By default prompts are displayed -literally, but if enabled with the \f3gl_prompt_style()\f1 -function (see later), prompts can contain directives to do -underlining, switch to and from bold fonts, or turn -highlighting on and off. - -If you want to specify the initial contents of the line, for -the user to edit, pass the desired string via the -\f3start_line\f1 argument. You can then specify which -character of this line the cursor is initially positioned -over, using the \f3start_pos\f1 argument. This should be -1 -if you want the cursor to follow the last character of the -start line. If you don't want to preload the line in this -manner, send \f3start_line\f1 as \f3NULL\f1, and set -\f3start_pos\f1 to -1. - -The \f3gl_get_line()\f1 function returns a pointer to the line entered -by the user, or \f3NULL\f1 on error or at the end of the input. The -returned pointer is part of the specified \f3gl\f1 resource object, -and thus should not be free'd 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 \f3gl_get_line()\f1 again to read the rest of the line. Note that -this behavior makes \f3gl_get_line()\f1 similar to \f3fgets()\f1. In -fact when \f3stdin\f1 isn't connected to a terminal,\f3gl_get_line()\f1 -just calls \f3fgets()\f1. - -.SH OPTIONAL PROMPT FORMATTING - -Whereas by default the prompt string that you specify is -displayed literally, without any special interpretation of -the characters within it, the \f3gl_prompt_style()\f1 -function can be used to enable optional formatting -directives within the prompt. -.sp -.nf - void gl_prompt_style(GetLine *gl, GlPromptStyle style); -.fi -.sp -The \f3style\f1 argument, which specifies the formatting -style, can take any of the following values: -.sp -.nf - GL_FORMAT_PROMPT - In this style, the formatting - directives described below, when - included in prompt strings, are - interpreted as follows: - - %B - Display subsequent - characters with a bold - font. - %b - Stop displaying characters - with the bold font. - %F - Make subsequent characters - flash. - %f - Turn off flashing - characters. - %U - Underline subsequent - characters. - %u - Stop underlining - characters. - %P - Switch to a pale (half - brightness) font. - %p - Stop using the pale font. - %S - Highlight subsequent - characters (also known as - standout mode). - %s - Stop highlighting - characters. - %V - Turn on reverse video. - %v - Turn off reverse video. - %% - Display a single % - character. - - For example, in this mode, a prompt - string like \f3"%UOK%u$ "\f1 would - display the prompt \f3"OK$ "\f1, - but with the \f3OK\f1 part - underlined. - - Note that although a pair of - characters that starts with a % - character, but doesn't match any of - the above directives is displayed - literally, if a new directive is - subsequently introduced which does - match, the displayed prompt will - change, so it is better to always - use %% to display a literal %. - - Also note that not all terminals - support all of these text - attributes, and that some substitute - a different attribute for missing - ones. - - GL_LITERAL_PROMPT - In this style, the prompt string is - printed literally. This is the - default style. -.fi -.sp - -.SH THE AVAILABLE KEY BINDING FUNCTIONS - -The \f3gl_get_line()\f1 function provides a number of functions which -can be bound to key sequences. The names of these functions, and what -they do, are given below. - -.nf - user-interrupt - Send a SIGINT signal to the - parent process. - abort - Send a SIGABRT signal to the - parent process. - suspend - Suspend the parent process. - stop-output - Pause terminal output. - start-output - Resume paused terminal output. - literal-next - Arrange for the next character - to be treated as a normal - character. This allows control - characters to be entered. - cursor-right - Move the cursor one character - right. - cursor-left - Move the cursor one character - left. - insert-mode - Toggle between insert mode and - overwrite mode. - beginning-of-line - Move the cursor to the - beginning of the line. - end-of-line - Move the cursor to the end of - the line. - delete-line - Delete the contents of the - current line. - kill-line - Delete everything that follows - the cursor. - backward-kill-line - Delete all characters between - the cursor and the start of the - line. - forward-word - Move to the end of the word - which follows the cursor. - forward-to-word - Move the cursor to the start of - the word that follows the - cursor. - backward-word - Move to the start of the word - which precedes the cursor. - goto-column - Move the cursor to the - 1-relative column in the line - specified by any preceding - digit-argument sequences (see - ENTERING REPEAT COUNTS below). - find-parenthesis - 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. - forward-delete-char - Delete the character under the - cursor. - backward-delete-char - Delete the character which - precedes the cursor. - list-or-eof - This is intended for binding - to ^D. When invoked when the - cursor is within the line it - displays all possible - completions then redisplays - the line unchanged. When - invoked on an empty line, it - signals end-of-input (EOF) to - the caller of gl_get_line(). - del-char-or-list-or-eof - This is intended for binding - to ^D. When invoked when the - cursor is within the line it - invokes forward-delete-char. - When invoked at the end of the - line it displays all possible - completions then redisplays - the line unchanged. When - invoked on an empty line, it - signals end-of-input (EOF) to - the caller of gl_get_line(). - forward-delete-word - Delete the word which follows - the cursor. - backward-delete-word - Delete the word which precedes - the cursor. - upcase-word - Convert all of the characters - of the word which follows the - cursor, to upper case. - downcase-word - Convert all of the characters - of the word which follows the - cursor, to lower case. - capitalize-word - Capitalize the word which - follows the cursor. - change-case - If the next character is upper - case, toggle it to lower case - and vice versa. - redisplay - Redisplay the line. - clear-screen - Clear the terminal, then - redisplay the current line. - transpose-chars - Swap the character under the - cursor with the character just - before the cursor. - set-mark - Set a mark at the position of - the cursor. - exchange-point-and-mark - Move the cursor to the last - mark that was set, and move - the mark to where the cursor - used to be. - kill-region - Delete the characters that lie - between the last mark that was - set, and the cursor. - copy-region-as-kill - Copy the text between the mark - and the cursor to the cut - buffer, without deleting the - original text. - yank - Insert the text that was last - deleted, just before the - current position of the cursor. - append-yank - Paste the current contents of - the cut buffer, after the - cursor. - up-history - Recall the next oldest line - that was entered. Note that - in vi mode you are left in - command mode. - down-history - Recall the next most recent - line that was entered. If no - history recall session is - currently active, the next - line from a previous recall - session is recalled. Note that - in vi mode you are left in - command mode. - history-search-backward - Recall the next oldest line - who's prefix matches the string - which currently precedes the - cursor (in vi command-mode the - character under the cursor is - also included in the search - string). Note that in vi mode - you are left in command mode. - history-search-forward - Recall the next newest line - who's prefix matches the string - which currently precedes the - cursor (in vi command-mode the - character under the cursor is - also included in the search - string). Note that in vi mode - you are left in command mode. - history-re-search-backward -Recall the next oldest line - who's prefix matches that - established by the last - invocation of either - history-search-forward or - history-search-backward. - history-re-search-forward - Recall the next newest line - who's prefix matches that - established by the last - invocation of either - history-search-forward or - history-search-backward. - complete-word - Attempt to complete the - incomplete word which - precedes the cursor. Unless - the host program has customized - word completion, filename - completion is attempted. In vi - commmand mode the character - under the cursor is also - included in the word being - completed, and you are left in - vi insert mode. - expand-filename - Within the command line, expand - wild cards, tilde expressions - and dollar expressions in the - filename which immediately - precedes the cursor. In vi - commmand mode the character - under the cursor is also - included in the filename being - expanded, and you are left in - vi insert mode. - list-glob - List any filenames which match - the wild-card, tilde and dollar - expressions in the filename - which immediately precedes the - cursor, then redraw the input - line unchanged. - list-history - Display the contents of the - history list for the current - history group. If a repeat - count of > 1 is specified, - only that many of the most - recent lines are displayed. - See the "ENTERING REPEAT - COUNTS" section. - read-from-file - Temporarily switch to reading - input from the file who's - name precedes the cursor. - read-init-files - Re-read teclarc configuration - files. - beginning-of-history - Move to the oldest line in the - history list. Note that in vi - mode you are left in command - mode. - end-of-history - Move to the newest line in the - history list (ie. the current - line). Note that in vi mode - this leaves you in command - mode. - digit-argument - Enter a repeat count for the - next key-binding function. - For details, see the ENTERING - REPEAT COUNTS section. - newline - Terminate and return the - current contents of the - line, after appending a - newline character. The newline - character is normally '\\n', - but will be the first - character of the key-sequence - that invoked the newline - action, if this happens to be - a printable character. If the - action was invoked by the - '\\n' newline character or the - '\\r' carriage return - character, the line is - appended to the history - buffer. - repeat-history - Return the line that is being - edited, then arrange for the - next most recent entry in the - history buffer to be recalled - when \f3gl_get_line()\f1 is - next called. Repeatedly - invoking this action causes - successive historical input - lines to be re-executed. Note - that this action is equivalent - to the 'Operate' action in - ksh. - ring-bell - Ring the terminal bell, unless - the bell has been silenced via - the \f3nobeep\f1 configuration - option (see the THE TECLA - CONFIGURATION FILE section). - forward-copy-char - Copy the next character into - the cut buffer (NB. use repeat - counts to copy more than one). - backward-copy-char - Copy the previous character - into the cut buffer. - forward-copy-word - Copy the next word into the cut - buffer. - backward-copy-word - Copy the previous word into the - cut buffer. - forward-find-char - Move the cursor to the next - occurrence of the next - character that you type. - backward-find-char - Move the cursor to the last - occurrence of the next - character that you type. - forward-to-char - Move the cursor to the - character just before the next - occurrence of the next - character that the user types. - backward-to-char - Move the cursor to the - character just after the last - occurrence before the cursor - of the next character that the - user types. - repeat-find-char - Repeat the last - backward-find-char, - forward-find-char, - backward-to-char or - forward-to-char. - invert-refind-char - Repeat the last - backward-find-char, - forward-find-char, - backward-to-char, or - forward-to-char in the - opposite direction. - delete-to-column - Delete the characters from the - cursor up to the column that - is specified by the repeat - count. - delete-to-parenthesis - Delete the characters from the - cursor up to and including - the matching parenthesis, or - next close parenthesis. - forward-delete-find - Delete the characters from the - cursor up to and including the - following occurence of the - next character typed. - backward-delete-find - Delete the characters from the - cursor up to and including the - preceding occurence of the - next character typed. - forward-delete-to - Delete the characters from the - cursor up to, but not - including, the following - occurence of the next - character typed. - backward-delete-to - Delete the characters from the - cursor up to, but not - including, the preceding - occurence of the next - character typed. - delete-refind - Repeat the last *-delete-find - or *-delete-to action. - delete-invert-refind - Repeat the last *-delete-find - or *-delete-to action, in the - opposite direction. - copy-to-column - Copy the characters from the - cursor up to the column that - is specified by the repeat - count, into the cut buffer. - copy-to-parenthesis - Copy the characters from the - cursor up to and including - the matching parenthesis, or - next close parenthesis, into - the cut buffer. - forward-copy-find - Copy the characters from the - cursor up to and including the - following occurence of the - next character typed, into the - cut buffer. - backward-copy-find - Copy the characters from the - cursor up to and including the - preceding occurence of the - next character typed, into the - cut buffer. - forward-copy-to - Copy the characters from the - cursor up to, but not - including, the following - occurence of the next - character typed, into the cut - buffer. - backward-copy-to - Copy the characters from the - cursor up to, but not - including, the preceding - occurence of the next - character typed, into the cut - buffer. - copy-refind - Repeat the last *-copy-find - or *-copy-to action. - copy-invert-refind - Repeat the last *-copy-find - or *-copy-to action, in the - opposite direction. - vi-mode - Switch to vi mode from emacs - mode. - emacs-mode - Switch to emacs mode from vi - mode. - vi-insert - From vi command mode, switch to - insert mode. - vi-overwrite - From vi command mode, switch to - overwrite mode. - vi-insert-at-bol - From vi command mode, move the - cursor to the start of the line - and switch to insert mode. - vi-append-at-eol - From vi command mode, move the - cursor to the end of the line - and switch to append mode. - vi-append - From vi command mode, move the - cursor one position right, and - switch to insert mode. - vi-replace-char - From vi command mode, replace - the character under the cursor - with the the next character - entered. - vi-forward-change-char - From vi command mode, delete - the next character then enter - insert mode. - vi-backward-change-char - From vi command mode, delete - the preceding character then - enter insert mode. - vi-forward-change-word - From vi command mode, delete - the next word then enter - insert mode. - vi-backward-change-word - From vi command mode, delete - the preceding word then - enter insert mode. - vi-change-rest-of-line - From vi command mode, delete - from the cursor to the end of - the line, then enter insert - mode. - vi-change-line - From vi command mode, delete - the current line, then enter - insert mode. - vi-change-to-bol - From vi command mode, delete - all characters between the - cursor and the beginning of - the line, then enter insert - mode. - vi-change-to-column - From vi command mode, delete - the characters from the cursor - up to the column that is - specified by the repeat count, - then enter insert mode. - vi-change-to-parenthesis - Delete the characters from the - cursor up to and including - the matching parenthesis, or - next close parenthesis, then - enter vi insert mode. - vi-forward-change-find - From vi command mode, delete - the characters from the - cursor up to and including the - following occurence of the - next character typed, then - enter insert mode. - vi-backward-change-find - From vi command mode, delete - the characters from the - cursor up to and including the - preceding occurence of the - next character typed, then - enter insert mode. - vi-forward-change-to - From vi command mode, delete - the characters from the - cursor up to, but not - including, the following - occurence of the next - character typed, then enter - insert mode. - vi-backward-change-to - From vi command mode, delete - the characters from the - cursor up to, but not - including, the preceding - occurence of the next - character typed, then enter - insert mode. - vi-change-refind - Repeat the last - vi-*-change-find or - vi-*-change-to action. - vi-change-invert-refind - Repeat the last - vi-*-change-find or - vi-*-change-to action, in the - opposite direction. - vi-undo - In vi mode, undo the last - editing operation. - vi-repeat-change - In vi command mode, repeat the - last command that modified the - line. -.fi - -.SH DEFAULT KEY BINDINGS IN EMACS MODE - -The following default key bindings, which can be overriden by -the tecla configuration file, are designed to mimic most of -the bindings of the unix \f3tcsh\f1 shell, when it is in -emacs editing mode. -.sp -This is the default editing mode of the tecla library. -.sp -Note that a key sequence like \f3^A\f1 or \f3C-a\f1 means hold the control-key -down while pressing the letter \f3A\f1, and that where you see \f3\\E\f1 or -\f3M-\f1 in a binding, this represents the escape key or the Meta modifier -key. Also note that to \f3gl_get_line()\f1, pressing the escape key before a -key is equivalent to pressing the meta key at the same time as that key. Thus -the key sequence \f3M-p\f1 can be typed in two ways, by pressing the escape -key, followed by pressing \f3p\f1, or by pressing the Meta key at the same time -as \f3p\f1. -.sp -Under UNIX the terminal driver sets a number of special keys for certain -functions. The tecla library attempts to use the same keybindings to maintain -consistency. The key sequences shown for the following 6 bindings are thus just -examples of what they will probably be set to. If you have used the \f3stty\f1 -command to change these keys, then the default bindings should match. - -.nf - ^C -> user-interrupt - ^\\ -> abort - ^Z -> suspend - ^Q -> start-output - ^S -> stop-output - ^V -> literal-next -.fi - -The cursor keys are refered to by name, as follows. This is necessary -because different types of terminals generate different key sequences -when their cursor keys are pressed. - - right -> cursor-right - left -> cursor-left - up -> up-history - down -> down-history - -The remaining bindings don't depend on the terminal setttings. - -.nf - ^F -> cursor-right - ^B -> cursor-left - M-i -> insert-mode - ^A -> beginning-of-line - ^E -> end-of-line - ^U -> delete-line - ^K -> kill-line - M-f -> forward-word - M-b -> backward-word - ^D -> del-char-or-list-or-eof - ^H -> backward-delete-char - ^? -> backward-delete-char - M-d -> forward-delete-word - M-^H -> backward-delete-word - M-^? -> backward-delete-word - M-u -> upcase-word - M-l -> downcase-word - M-c -> capitalize-word - ^R -> redisplay - ^L -> clear-screen - ^T -> transpose-chars - ^@ -> set-mark - ^X^X -> exchange-point-and-mark - ^W -> kill-region - M-w -> copy-region-as-kill - ^Y -> yank - ^P -> up-history - ^N -> down-history - M-p -> history-search-backward - M-n -> history-search-forward - ^I -> complete-word - ^X* -> expand-filename - ^X^F -> read-from-file - ^X^R -> read-init-files - ^Xg -> list-glob - ^Xh -> list-history - M-< -> beginning-of-history - M-> -> end-of-history - \\n -> newline - \\r -> newline - M-o -> repeat-history - M-^V -> vi-mode - - M-0, M-1, ... M-9 -> digit-argument (see below) -.fi - -Note that ^I is what the TAB key generates, and that ^@ can be -generated not only by pressing the control key and the @ key -simultaneously, but also by pressing the control key and the space bar -at the same time. - -.SH DEFAULT KEY BINDINGS IN VI MODE - -The following default key bindings are designed to mimic the -vi style of editing as closely as possible. This means that -very few editing functions are provided in the initial -character input mode, editing functions instead being -provided by the vi command mode. Vi command mode is entered -whenever the escape character is pressed, or whenever a -key-sequence that starts with a meta character is entered. In -addition to mimicing vi, libtecla provides bindings for tab -completion, wild-card expansion of file names, and historical -line recall. -.sp -To learn how to tell the tecla library to use vi mode instead -of the default emacs editing mode, see the section entitled -THE TECLA CONFIGURATION FILE. -.sp -As already mentioned above in the emacs section, Note that a -key sequence like \f3^A\f1 or \f3C-a\f1 means hold the -control-key down while pressing the letter \f3A\f1, and that -where you see \f3\\E\f1 or \f3M-\f1 in a binding, this -represents the escape key or the Meta modifier key. Also note -that to \f3gl_get_line()\f1, pressing the escape key before a -key is equivalent to pressing the meta key at the same time -as that key. Thus the key sequence \f3M-p\f1 can be typed in -two ways, by pressing the escape key, followed by pressing -\f3p\f1, or by pressing the Meta key at the same time as -\f3p\f1. -.sp -Under UNIX the terminal driver sets a number of special keys -for certain functions. The tecla library attempts to use the -same keybindings to maintain consistency, binding them both -in input mode and in command mode. The key sequences shown -for the following 6 bindings are thus just examples of what -they will probably be set to. If you have used the \f3stty\f1 -command to change these keys, then the default bindings -should match. - -.nf - ^C -> user-interrupt - ^\\ -> abort - ^Z -> suspend - ^Q -> start-output - ^S -> stop-output - ^V -> literal-next - M-^C -> user-interrupt - M-^\\ -> abort - M-^Z -> suspend - M-^Q -> start-output - M-^S -> stop-output -.fi - -Note that above, most of the bindings are defined twice, once -as a raw control code like \f3^C\f1 and then a second time as -a meta character like \f3M-^C\f1. The former is the binding -for vi input mode, whereas the latter is the binding for vi -command mode. Once in command mode all key-sequences that the -user types that they don't explicitly start with an escape or -a meta key, have their first key secretly converted to a meta -character before the key sequence is looked up in the key -binding table. Thus, once in command mode, when you type the -letter \f3i\f1, for example, the tecla library actually looks -up the binding for \f3M-i\f1. - -The cursor keys are refered to by name, as follows. This is necessary -because different types of terminals generate different key sequences -when their cursor keys are pressed. - - right -> cursor-right - left -> cursor-left - up -> up-history - down -> down-history - -The cursor keys normally generate a keysequence that start -with an escape character, so beware that using the arrow keys -will put you into command mode (if you aren't already in -command mode). -.sp -The following are the terminal-independent key bindings for vi input -mode. - -.nf - ^D -> list-or-eof - ^G -> list-glob - ^H -> backward-delete-char - ^I -> complete-word - \\r -> newline - \\n -> newline - ^L -> clear-screen - ^N -> down-history - ^P -> up-history - ^R -> redisplay - ^U -> backward-kill-line - ^W -> backward-delete-word - ^X* -> expand-filename - ^X^F -> read-from-file - ^X^R -> read-init-files - ^? -> backward-delete-char -.fi - -The following are the key bindings that are defined in vi -command mode, this being specified by them all starting with -a meta character. As mentioned above, once in command mode -the initial meta character is optional. For example, you -might enter command mode by typing Esc, and then press h -twice to move the cursor two positions to the left. Both h -characters get quietly converted to M-h before being compared -to the key-binding table, the first one because Escape -followed by a character is always converted to the equivalent -meta character, and the second because command mode was -already active. - -.nf - M-\\ -> cursor-right (Meta-space) - M-$ -> end-of-line - M-* -> expand-filename - M-+ -> down-history - M-- -> up-history - M-< -> beginning-of-history - M-> -> end-of-history - M-^ -> beginning-of-line - M-; -> repeat-find-char - M-, -> invert-refind-char - M-| -> goto-column - M-~ -> change-case - M-. -> vi-repeat-change - M-% -> find-parenthesis - M-a -> vi-append - M-A -> vi-append-at-eol - M-b -> backward-word - M-B -> backward-word - M-C -> vi-change-rest-of-line - M-cb -> vi-backward-change-word - M-cB -> vi-backward-change-word - M-cc -> vi-change-line - M-ce -> vi-forward-change-word - M-cE -> vi-forward-change-word - M-cw -> vi-forward-change-word - M-cW -> vi-forward-change-word - M-cF -> vi-backward-change-find - M-cf -> vi-forward-change-find - M-cT -> vi-backward-change-to - M-ct -> vi-forward-change-to - M-c; -> vi-change-refind - M-c, -> vi-change-invert-refind - M-ch -> vi-backward-change-char - M-c^H -> vi-backward-change-char - M-c^? -> vi-backward-change-char - M-cl -> vi-forward-change-char - M-c\\ -> vi-forward-change-char (Meta-c-space) - M-c^ -> vi-change-to-bol - M-c0 -> vi-change-to-bol - M-c$ -> vi-change-rest-of-line - M-c| -> vi-change-to-column - M-c% -> vi-change-to-parenthesis - M-dh -> backward-delete-char - M-d^H -> backward-delete-char - M-d^? -> backward-delete-char - M-dl -> forward-delete-char - M-d -> forward-delete-char (Meta-d-space) - M-dd -> delete-line - M-db -> backward-delete-word - M-dB -> backward-delete-word - M-de -> forward-delete-word - M-dE -> forward-delete-word - M-dw -> forward-delete-word - M-dW -> forward-delete-word - M-dF -> backward-delete-find - M-df -> forward-delete-find - M-dT -> backward-delete-to - M-dt -> forward-delete-to - M-d; -> delete-refind - M-d, -> delete-invert-refind - M-d^ -> backward-kill-line - M-d0 -> backward-kill-line - M-d$ -> kill-line - M-D -> kill-line - M-d| -> delete-to-column - M-d% -> delete-to-parenthesis - M-e -> forward-word - M-E -> forward-word - M-f -> forward-find-char - M-F -> backward-find-char - M-- -> up-history - M-h -> cursor-left - M-H -> beginning-of-history - M-i -> vi-insert - M-I -> vi-insert-at-bol - M-j -> down-history - M-J -> history-search-forward - M-k -> up-history - M-K -> history-search-backward - M-l -> cursor-right - M-L -> end-of-history - M-n -> history-re-search-forward - M-N -> history-re-search-backward - M-p -> append-yank - M-P -> yank - M-r -> vi-replace-char - M-R -> vi-overwrite - M-s -> vi-forward-change-char - M-S -> vi-change-line - M-t -> forward-to-char - M-T -> backward-to-char - M-u -> vi-undo - M-w -> forward-to-word - M-W -> forward-to-word - M-x -> forward-delete-char - M-X -> backward-delete-char - M-yh -> backward-copy-char - M-y^H -> backward-copy-char - M-y^? -> backward-copy-char - M-yl -> forward-copy-char - M-y\\ -> forward-copy-char (Meta-y-space) - M-ye -> forward-copy-word - M-yE -> forward-copy-word - M-yw -> forward-copy-word - M-yW -> forward-copy-word - M-yb -> backward-copy-word - M-yB -> backward-copy-word - M-yf -> forward-copy-find - M-yF -> backward-copy-find - M-yt -> forward-copy-to - M-yT -> backward-copy-to - M-y; -> copy-refind - M-y, -> copy-invert-refind - M-y^ -> copy-to-bol - M-y0 -> copy-to-bol - M-y$ -> copy-rest-of-line - M-yy -> copy-line - M-Y -> copy-line - M-y| -> copy-to-column - M-y% -> copy-to-parenthesis - M-^E -> emacs-mode - M-^H -> cursor-left - M-^? -> cursor-left - M-^L -> clear-screen - M-^N -> down-history - M-^P -> up-history - M-^R -> redisplay - M-^D -> list-or-eof - M-^I -> complete-word - M-\\r -> newline - M-\\n -> newline - M-^X^R -> read-init-files - M-^Xh -> list-history - - M-0, M-1, ... M-9 -> digit-argument (see below) -.fi - -Note that ^I is what the TAB key generates. - -.SH ENTERING REPEAT COUNTS - -Many of the key binding functions described previously, take -an optional count, typed in before the target -keysequence. This is interpreted as a repeat count by most -bindings. A notable exception is the goto-column binding, -which interprets the count as a column number. -.sp -By default you can specify this count argument by pressing -the meta key while typing in the numeric count. This relies -on the \f3digit-argument\f1 action being bound to Meta-0, -Meta-1 etc. Once any one of these bindings has been -activated, you can optionally take your finger off the meta -key to type in the rest of the number, since every numeric -digit thereafter is treated as part of the number, unless it -is preceded by the \f3literal-next\f1 binding. As soon as a -non-digit, or literal digit key is pressed the repeat count -is terminated and either causes the just typed character to -be added to the line that many times, or causes the next -key-binding function to be given that argument. -.sp -For example, in emacs mode, typing: -.sp -.nf - M-12a -.fi -.sp -causes the letter 'a' to be added to the line 12 times, -whereas -.sp -.nf - M-4M-c -.fi -.sp -Capitalizes the next 4 words. -.sp -In vi command mode the Meta modifier is automatically added -to all characters typed in, so to enter a count in vi -command-mode, just involves typing in the number, just as at -it does in the vi editor itself. So for example, in vi -command mode, typing: -.sp -.nf - 4w2x -.fi -.sp -moves the cursor four words to the right, then deletes two characters. -.sp -You can also bind \f3digit-argument\f1 to other key sequences. If -these end in a numeric digit, that digit gets appended to the current -repeat count. If it doesn't end in a numeric digit, a new repeat count -is started with a value of zero, and can be completed by typing in the -number, after letting go of the key which triggered the digit-argument -action. - -.SH THE TECLA CONFIGURATION FILE - -By default, the first call to \f3gl_get_line()\f1 looks for a file -called \f3\&.teclarc\f1 in your home directory (ie. \f3~/.teclarc\f1). -If it finds this file, it reads it, interpreting each line as defining -a new key binding or an editing configuration option. Since the emacs -keybindings are installed by default, if you want to use the -non-default vi editing mode, the most important item to go in this -file is the following line: - -.nf - edit-mode vi -.fi - -This will re-configure the default bindings for vi-mode. The -complete set of arguments that this command accepts are: -.sp -.nf - vi - Install key-bindings like those of the vi - editor. - emacs - Install key-bindings like those of the emacs - editor. This is the default. - none - Use just the native line editing facilities - provided by the terminal driver. -.fi -.sp -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: - -.nf - nobeep -.fi - -An example of a key binding line in the configuration file is -the following. - -.nf - bind M-[2~ insert-mode -.fi - -On many keyboards, the above key sequence is generated when one -presses the \f3insert\f1 key, so with this keybinding, one can toggle -between the emacs-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 \f3M-\f1 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. - -.nf - 1. Hit the escape key momentarily, then press '[', then '2', then - finally '~'. - - 2. Press the meta key at the same time as pressing the '[' key, - then press '2', then '~'. -.fi - -If you set a keybinding 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 -Starting with versions of libtecla later than 1.3.3 it is now possible -to bind keysequences that begin with a printable character. Previously -key-sequences were required to start with a control or meta character. -.sp -Note that the special keywords "up", "down", "left" and "right" refer -to the arrow keys, and are thus not treated as keysequences. 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: - -.nf - bind up history-search-backwards - bind down history-search-backwards -.fi -.sp -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 ^A key sequence: - -.nf - bind ^A -.fi - -.SH ALTERNATE CONFIGURATION SOURCES - -As mentioned above, by default users have the option of configuring -the behavior of \f3gl_get_line()\f1 via a configuration file called -\f3\&.teclarc\f1 in their home directories. The fact that all -applications share this same configuration file is both an advantage -and a disadvantage. In most cases it is an advantage, since it -encourages uniformity, and frees the user from having to configure -each application separately. In some applications, however, this -single means of configuration is a problem. This is particularly true -of embedded software, where there's no filesystem to read a -configuration file from, and also in applications where a radically -different choice of keybindings is needed to emulate a legacy keyboard -interface. To cater for such cases, the following function allows the -application to control where configuration information is read from. - -.sp -.nf - int gl_configure_getline(GetLine *gl, - const char *app_string, - const char *app_file, - const char *user_file); -.fi -.sp - -It allows the configuration commands that would normally be read from -a user's \f3~/.teclarc\f1 file, to be read from any or none of, a -string, an application specific configuration file, and/or a -user-specific configuration file. If this function is called before -the first call to \f3gl_get_line()\f1, the default behavior of -reading \f3~/.teclarc\f1 on the first call to \f3gl_get_line()\f1 is -disabled, so all configuration must be achieved using the -configuration sources specified with this function. - -If \f3app_string != NULL\f1, then it is interpreted as a string -containing one or more configuration commands, separated from each -other in the string by embedded newline characters. If \f3app_file != -NULL\f1 then it is interpreted as the full pathname of an -application-specific configuration file. If \f3user_file != NULL\f1 -then it is interpreted as the full pathname of a user-specific -configuration file, such as \f3~/.teclarc\f1. For example, in the -following call, - - gl_configure_getline(gl, "edit-mode vi \\n nobeep", - "/usr/share/myapp/teclarc", - "~/.teclarc"); - -the \f3app_string\f1 argument causes the calling application to start -in vi edit-mode, instead of the default emacs mode, and turns off the -use of the terminal bell by the library. It then attempts to read -system-wide configuration commands from an optional file called -\f3/usr/share/myapp/teclarc\f1, then finally reads user-specific -configuration commands from an optional \f3\&.teclarc\f1 file in the -user's home directory. Note that the arguments are listed in ascending -order of priority, with the contents of \f3app_string\f1 being -potentially overriden by commands in \f3app_file\f1, and commands in -\f3app_file\f1 potentially being overriden by commands in -\f3user_file\f1. -.sp -You can call this function as many times as needed, the results being -cumulative, but note that copies of any filenames specified via the -\f3app_file\f1 and \f3user_file\f1 arguments are recorded internally -for subsequent use by the \f3read-init-files\f1 key-binding function, -so if you plan to call this function multiple times, be sure that the -last call specifies the filenames that you want re-read when the user -requests that the configuration files be re-read. - -.SH FILENAME AND TILDE COMPLETION - -With the default key bindings, pressing the TAB key (aka. ^I) results -in \f3gl_get_line()\f1 attempting to complete the incomplete filename -that precedes the cursor. \f3gl_get_line()\f1 searches backwards from -the cursor, looking for the start of the filename, stopping when it -hits either a space or the start of the line. If more than one file -has the specified prefix, \f3gl_get_line()\f1 completes the filename -up to the point at which the ambiguous matches start to differ, then -lists the possible matches. -.sp -In addition to literally written filenames, \f3gl_get_line()\f1 can -complete files that start with \f3~/\f1 and \f3~user/\f1 expressions -and that contain \f3$envvar\f1 expressions. In particular, if you hit -TAB within an incomplete \f3~user\f1, expression, \f3gl_get_line()\f1 -will attempt to complete the username, listing any ambiguous matches. -.sp -The completion binding is implemented using the -\f3cpl_word_completions()\f1 function, which is also available -separately to users of this library. See the -\f3cpl_word_completions(3)\f1 man page for more details. - -.SH CUSTOMIZED WORD COMPLETION - -If in your application, you would like to have TAB completion complete -other things in addition to or instead of filenames, you can arrange -this by registering an alternate completion callback function, via a -call to the \f3gl_customize_completion()\f1 function. -.sp -.nf - int gl_customize_completion(GetLine *gl, void *data, - CplMatchFn *match_fn); -.fi -.sp -The \f3data\f1 argument provides a way for your application to pass -arbitrary, application-specific information to the callback -function. This is passed to the callback every time that it is -called. It might for example, point to the symbol table from which -possible completions are to be sought. The \f3match_fn\f1 argument -specifies the callback function to be called. The \f3CplMatchFn\f1 -function type is defined in \f3libtecla.h\f1, as is a -\f3CPL_MATCH_FN()\f1 macro that you can use to declare and prototype -callback functions. The declaration and responsibilities of callback -functions are described in depth in the \f1cpl_complete_word(3)\f1 man -page. -.sp -In brief, the callback function is responsible for looking backwards -in the input line, back from the point at which the user pressed TAB, -to find the start of the word being completed. It then must lookup -possible completions of this word, and record them one by one in the -\f3WordCompletion\f1 object that is passed to it as an argument, by -calling the \f3cpl_add_completion()\f1 function. If the callback -function wishes to provide filename completion in addition to its own -specific completions, it has the option of itself calling the builtin -file-name completion callback. This also, is documented in the -\f3cpl_complete_word(3)\f1 man page. -.sp -Note that if you would like \f3gl_get_line()\f1 to return the current -input line when a successful completion is been made, you can arrange -this when you call \f3cpl_add_completion()\f1, by making the last -character of the continuation suffix a newline character. If you do -this, the input line will be updated to display the completion, -together with any contiuation suffix up to the newline character, then -\f3gl_get_line()\f1 will return this input line. - -.SH FILENAME EXPANSION - -With the default key bindings, pressing \f3^X*\f1 causes -\f3gl_get_line()\f1 to expand the filename that precedes the cursor, -replacing \f3~/\f1 and \f3~user/\f1 expressions with the corresponding -home directories, and replacing \f3$envvar\f1 expressions with the -value of the specified environment variable, then if there are any -wildcards, replacing the so far expanded filename with a -space-separated list of the files which match the wild cards. -.sp -The expansion binding is implemented using the \f3ef_expand_file()\f1 function. -See the \f3ef_expand_file(3)\f1 man page for more details. - -.SH RECALLING PREVIOUSLY TYPED LINES - -Every time that a new line is entered by the user, it is appended to a -list of historical input lines maintained within the GetLine 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 \f3^P\f1, and -\f3^N\f1 keys, and in vi 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 -Note that in vi mode, all of the history recall functions switch the -library into command mode. -.sp -In emacs mode the \f3M-p\f1 and \f3M-n\f1 keys work just like the -\f3^P\f1 and \f3^N\f1 keys, except that they skip all but those -historical lines which share the prefix that precedes the cursor. In -vi command mode the upper case \f3K\f1 and \f3J\f1 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 -Thus for example, suppose that you were in emacs mode, and you had -just entered the following list of commands in the order shown: - -.nf - ls ~/tecla/ - cd ~/tecla - ls -l getline.c - emacs ~/tecla/getline.c -.fi - -If you next typed: - -.nf - ls -.fi - -and then hit \f3M-p\f1, then rather than returning the previously -typed emacs line, which doesn't start with "ls", \f3gl_get_line()\f1 -would recall the "ls -l getline.c" line. Pressing \f3M-p\f1 again -would recall the "ls ~/tecla/" line. - -.SH HISTORY FILES - -To save the contents of the history buffer before quitting your -application, and subsequently restore them when you next start the -application, the following functions are provided. - -.sp -.nf - int gl_save_history(GetLine *gl, const char *filename, - const char *comment, int max_lines); - int gl_load_history(GetLine *gl, const char *filename, - const char *comment); -.fi -.sp - -The \f3filename\f1 argument specifies the name to give the history -file when saving, or the name of an existing history file, when -loading. This may contain home-directory and environment variable -expressions, such as "~/.myapp_history" or "$HOME/.myapp_history". -.sp -Along with each history line, extra information about it, such as when -it was entered by the user, and what its nesting level is, is recorded -as a comment preceding the line in the history file. Writing this as a -comment allows the history file to double as a command file, just in -case you wish to replay a whole session using it. Since comment -prefixes differ in different languages, the \f3comment\f1 argument is -provided for specifying the comment prefix. For example, if your -application were a unix shell, such as the bourne shell, you would -specify "#" here. Whatever you choose for the comment character, you -must specify the same prefix to \f3gl_load_history()\f1 that you used -when you called \f3gl_save_history()\f1 to write the history file. -.sp -The \f3max_lines\f1 must be either -1 to specify that all lines in the -history list be saved, or a positive number specifying a ceiling on -how many of the most recent lines should be saved. -.sp -Both fuctions return non-zero on error, after writing an error message -to stderr. Note that \f3gl_load_history()\f1 does not consider the -non-existence of a file to be an error. - -.SH MULTIPLE HISTORY LISTS - -If your application uses a single \f3GetLine\f1 object for entering -many different types of input lines, you may wish \f3gl_get_line()\f1 -to distinguish the different types of lines in the history list, and -only recall lines that match the current type of line. To support this -requirement, \f3gl_get_line()\f1 marks lines being recorded in the -history list with an integer identifier chosen by the application. -Initially this identifier is set to \f10\f3 by \f3new_GetLine()\f1, -but it can be changed subsequently by calling -\f3gl_group_history()\f1. - -.sp -.nf - int gl_group_history(GetLine *gl, unsigned id); -.fi -.sp - -The integer identifier \f3id\f1 can be any number chosen by the -application, but note that \f3gl_save_history()\f1 and -\f3gl_load_history()\f1 preserve the association between identifiers -and historical input lines between program invokations, so you should -choose fixed identifiers for the different types of input line used by -your application. -.sp -Whenever \f3gl_get_line()\f1 appends a new input line to the history -list, the current history identifier is recorded with it, and when it -is asked to recall a historical input line, it only recalls lines that -are marked with the current identifier. - -.SH DISPLAYING HISTORY - -The history list can be displayed by calling \f3gl_show_history()\f1. - -.sp -.nf - int gl_show_history(GetLine *gl, FILE *fp, - const char *fmt, - int all_groups, - int max_lines); -.fi -.sp - -This displays the current contents of the history list to the stdio -output stream \f3fp\f1. If the \f3max_lines\f1 argument is greater -than or equal to zero, then no more than this number of the most -recent lines will be displayed. If the \f3all_groups\f1 argument is -non-zero, lines from all history groups are displayed. Otherwise just -those of the currently selected history group are displayed. The -format string argument, \f3fmt\f1, determines how the line is -displayed. This can contain arbitrary characters which are written -verbatim, interleaved with any of the following format directives: - -.nf - %D - The date on which the line was originally - entered, formatted like 2001-11-20. - %T - The time of day when the line was entered, - formatted like 23:59:59. - %N - The sequential entry number of the line in - the history buffer. - %G - The number of the history group which the - line belongs to. - %% - A literal % character. - %H - The history line itself. -.fi - -Thus a format string like \f3"%D %T %H\n"\f1 would output something like: - -.nf - 2001-11-20 10:23:34 Hello world -.fi - -Note the inclusion of an explicit newline character in the format -string. - -.SH LOOKING UP HISTORY - -The \f3gl_lookup_history()\f1 function allows the calling application -to look up lines in the history list. - -.sp -.nf - typedef struct { - const char *line; /* The requested historical */ - /* line. */ - unsigned group; /* The history group to which */ - /* the line belongs. */ - time_t timestamp; /* The date and time at which */ - /* the line was originally */ - /* entered. */ - } GlHistoryLine; - - int gl_lookup_history(GetLine *gl, unsigned long id, - GlHistoryLine *hline); -.fi -.sp - -The \f3id\f1 argument indicates which line to look up, where the first -line that was entered in the history list after \f3new_GetLine()\f1 -was called, is denoted by 0, and subsequently entered lines are -denoted with successively higher numbers. Note that the range of lines -currently preserved in the history list can be queried by calling the -\f3gl_range_of_history()\f1 function, described later. If the -requested line is in the history list, the details of the line are -recorded in the variable pointed to by the \f3hline\f1 argument, and -\f31\f1 is returned. Otherwise \f30\f1 is returned, and the variable -pointed to by \f3hline\f1 is left unchanged. -.sp -Beware that the string returned in \f3hline->line\f1 is part of the -history buffer, so it must not be modified by the caller, and will be -recycled on the next call to any function that takes \f3gl\f1 as its -argument. Therefore you should make a private copy of this string if -you need to keep it around. - -.SH MISCELLANEOUS HISTORY CONFIGURATION - -If you wish to change the size of the history buffer that was -originally specified in the call to \f3new_GetLine()\f1, you can do so -with the \f3gl_resize_history()\f1 function. - -.sp -.nf - int gl_resize_history(GetLine *gl, size_t histlen); -.fi -.sp - -The \f3histlen\f1 argument specifies the new size in bytes, and if you -specify this as 0, the buffer will be deleted. -.sp -As mentioned in the discussion of \f3new_GetLine()\f1, the number of -lines that can be stored in the history buffer, depends on the lengths -of the individual lines. For example, a 1000 byte buffer could equally -store 10 lines of average length 100 bytes, or 2 lines of average -length 50 bytes. Although the buffer is never expanded when new lines -are added, a list of pointers into the buffer does get expanded when -needed to accomodate the number of lines currently stored in the -buffer. To place an upper limit on the number of lines in the buffer, -and thus a ceiling on the amount of memory used in this list, you can -call the \f3gl_limit_history()\f1 function. - -.sp -.nf - void gl_limit_history(GetLine *gl, int max_lines); -.fi -.sp - -The \f3max_lines\f1 should either be a positive number \f3>= 0\f1, -specifying an upper limit on the number of lines in the buffer, or be -\f3-1\f1 to cancel any previously specified limit. When a limit is in -effect, only the \f3max_lines\f1 most recently appended lines are kept -in the buffer. Older lines are discarded. -.sp -To discard lines from the history buffer, use the -\f3gl_clear_history()\f1 function. -.sp -.nf - void gl_clear_history(GetLine *gl, int all_groups); -.fi -.sp -The \f3all_groups\f1 argument tells the function whether to delete -just the lines associated with the current history group (see -\f3gl_group_history()\f1), or all historical lines in the buffer. -.sp -The \f3gl_toggle_history()\f1 function allows you to toggle history on -and off without losing the current contents of the history list. - -.sp -.nf - void gl_toggle_history(GetLine *gl, int enable); -.fi -.sp - -Setting the \f3enable\f1 argument to 0 turns off the history -mechanism, and setting it to 1 turns it back on. When history is -turned off, no new lines will be added to the history list, and -history lookup key-bindings will act as though there is nothing in the -history buffer. - -.SH QUERYING HISTORY INFORMATION - -The configured state of the history list can be queried with the -\f3gl_history_state()\f1 function. - -.sp -.nf - typedef struct { - int enabled; /* True if history is enabled */ - unsigned group; /* The current history group */ - int max_lines; /* The current upper limit on the */ - /* number of lines in the history */ - /* list, or -1 if unlimited. */ - } GlHistoryState; - - void gl_state_of_history(GetLine *gl, - GlHistoryState *state); -.fi -.sp -On return, the status information is recorded in the variable pointed -to by the \f3state\f1 argument. -.sp -The \f3gl_range_of_history()\f1 function returns the number and -range of lines in the history list. - -.sp -.nf -typedef struct { - unsigned long oldest; /* The sequential entry number */ - /* of the oldest line in the */ - /* history list. */ - unsigned long newest; /* The sequential entry number */ - /* of the newest line in the */ - /* history list. */ - int nlines; /* The number of lines in the */ - /* history list. */ -} GlHistoryRange; - -void gl_range_of_history(GetLine *gl, GlHistoryRange *range); -.fi -.sp -The return values are recorded in the variable pointed to by the -\f3range\f1 argument. If the \f3nlines\f1 member of this structure is -greater than zero, then the \f3oldest\f1 and \f3newest\f1 members -report the range of lines in the list, and \f3newest=oldest+nlines-1\f1. -Otherwise they are both zero. -.sp -The \f3gl_size_of_history()\f1 function returns the total size of the -history buffer and the amount of the buffer that is currently -occupied. -.sp -.nf - typedef struct { - size_t size; /* The size of the history buffer */ - /* (bytes). */ - size_t used; /* The number of bytes of the */ - /* history buffer that are */ - /* currently occupied. */ - } GlHistorySize; - - void gl_size_of_history(GetLine *gl, GlHistorySize *size); -.fi -.sp -On return, the size information is recorded in the variable pointed to -by the \f3size\f1 argument. - -.SH CHANGING TERMINALS - -The \f3new_GetLine()\f1 constructor function assumes that input is to -be read from \f3stdin\f1, and output written to \f3stdout\f1. The -following function allows you to switch to different input and output -streams. -.sp -.nf - int gl_change_terminal(GetLine *gl, FILE *input_fp, - FILE *output_fp, const char *term); -.fi -.sp -The \f3gl\f1 argument is the object that was returned by -\f3new_GetLine()\f1. The \f3input_fp\f1 argument specifies the stream -to read from, and \f3output_fp\f1 specifies the stream to be written -to. Only if both of these refer to a terminal, will interactive -terminal input be enabled. Otherwise \f3gl_get_line()\f1 will simply -call \f3fgets()\f1 to read command input. If both streams refer to a -terminal, then they must refer to the same terminal, and the type of -this terminal must be specified via the \f3term\f1 argument. The value -of the \f3term\f1 argument is looked up in the terminal information -database (terminfo or termcap), in order to determine which special -control sequences are needed to control various aspects of the -terminal. \f3new_GetLine()\f1 for example, passes the return value of -\f3getenv("TERM")\f1 in this argument. Note that if one or both of -\f3input_fp\f1 and \f3output_fp\f1 don't refer to a terminal, then it -is legal to pass \f3NULL\f1 instead of a terminal type. -.sp -Note that if you want to pass file descriptors to -\f3gl_change_terminal()\f1, you can do this by creating stdio stream -wrappers using the POSIX \f3fdopen()\f1 function. - -.SH EXTERNAL EVENT HANDLING - -While \f3gl_get_line()\f1 is waiting for keyboard input from the user, -you can ask it to also watch for activity on arbitrary file -descriptors, such as network sockets, pipes etc, and have it call -functions of your choosing when activity is seen. This works on any -system that has the \f3select()\f1 system call, which is most, if not -all flavors of unix. Registering a file descriptor to be watched by -\f3gl_get_line()\f1 involves calling the \f3gl_watch_fd()\f1 function. - -.sp -.nf - int gl_watch_fd(GetLine *gl, int fd, GlFdEvent event, - GlFdEventFn *callback, void *data); -.fi -.sp - -If this returns non-zero, then it means that either your arguments are -invalid, or that this facility isn't supported on the host system. -.sp -The \f3fd\f1 argument is the file descriptor to be watched. The -\f3event\f1 argument specifies what type of activity is of interest, -chosen from the following enumerated values: - -.sp -.nf - GLFD_READ - Watch for the arrival of data to be read. - GLFD_WRITE - Watch for the ability to write to the file - descriptor without blocking. - GLFD_URGENT - Watch for the arrival of urgent - out-of-band data on the file descriptor. -.fi -.sp - -The \f3callback\f1 argument is the function to call when the selected -activity is seen. It should be defined with the following macro, which -is defined in libtecla.h. - -.sp -.nf - #define GL_FD_EVENT_FN(fn) GlFdStatus (fn)(GetLine *gl, \\ - void *data, int fd, \\ - GlFdEvent event) -.fi -.sp -The \f3data\f1 argument of the \f3gl_watch_fd()\f1 function is passed -to the callback function for its own use, and can point to anything -you like, including \f3NULL\f1. The file descriptor and the event -argument are also passed to the callback function, and this -potentially allows the same callback function to be registered to more -than one type of event and/or more than one file descriptor. The -return value of the callback function should be one of the following -values. - -.sp -.nf - GLFD_ABORT - Tell gl_get_line() to abort with an - error (errno won't be set, so set it - appropriately yourself if you need it). - GLFD_REFRESH - Redraw the input line then continue - waiting for input. Return this if - your callback wrote to the terminal. - GLFD_CONTINUE - Continue to wait for input, without - redrawing the line. -.fi -.sp -Note that before calling the callback, \f3gl_get_line()\f1 blocks most -signals, and leaves its own signal handlers installed, so if you need -to catch a particular signal you will need to both temporarily install -your own signal handler, and unblock the signal. Be sure to re-block -the signal (if it was originally blocked) and reinstate the original -signal handler, if any, before returning. -.sp -Your callback shouldn't try to read from the terminal, which is left -in raw mode as far as input is concerned. You can however write to the -terminal as usual, since features like conversion of newline to -carriage-return/linefeed are re-enabled while the callback is -running. If your callback function does write to the terminal, be sure -to output a newline first, and when your callback returns, tell -\f3gl_get_line()\f1 that the input line needs to be redrawn, by -returning the \f3GLFD_REFRESH\f1 status code. -.sp -To remove a callback function that you previously registered for a -given file descriptor and event, simply call \f3gl_watch_fd()\f1 with -the same file descriptor and \f3event\f1 arguments, but with a -\f3callback\f1 argument of \f30\f1. The \f3data\f1 argument is ignored -in this case. - -.SH SIGNAL HANDLING DEFAULTS - -By default, the \f3gl_get_line()\f1 function intercepts a -number of signals. This is particularly important for -signals which would by default terminate the process, since -the terminal needs to be restored to a usable state before -this happens. In this section, the signals that are trapped -by default, and how gl_get_line() responds to them, is -described. Changing these defaults is the topic of the -following section. -.sp -When the following subset of signals are caught, \f3gl_get_line()\f1 -first restores the terminal settings and signal handling to how they -were before \f3gl_get_line()\f1 was called, resends the signal, to -allow the calling application's signal handlers to handle it, then if -the process still exists, \f3gl_get_line()\f1 returns \f3NULL\f1 and -sets \f3errno\f1 as specified below. - -.sp -.nf - SIGINT - This signal is generated both by the keyboard - interrupt key (usually ^C), and the keyboard - break key. - - errno=EINTR - - SIGHUP - This signal is generated when the controlling - terminal exits. - - errno=ENOTTY - - SIGPIPE - This signal is generated when a program attempts - to write to a pipe who's remote end isn't being - read by any process. This can happen for example - if you have called \f3gl_change_terminal()\f1 to - redirect output to a pipe hidden under a pseudo - terminal. - - errno=EPIPE - - SIGQUIT - This signal is generated by the keyboard quit - key (usually ^\\). - - errno=EINTR - - SIGABRT - This signal is generated by the standard C, - abort() function. By default it both - terminates the process and generates a core - dump. - - errno=EINTR - - SIGTERM - This is the default signal that the UN*X - kill command sends to processes. - - errno=EINTR -.fi -.sp -Note that in the case of all of the above signals, POSIX mandates that -by default the process is terminated, with the addition of a core dump -in the case of the \f3SIGQUIT\f1 signal. In other words, if the -calling application doesn't override the default handler by supplying -its own signal handler, receipt of the corresponding signal will -terminate the application before \f3gl_get_line()\f1 returns. -.sp -If gl_get_line() aborts with errno set to EINTR, you can find out what -signal caused it to abort, by calling the following function. -.sp -.nf - int gl_last_signal(const GetLine *gl); -.fi -.sp -This returns the numeric code (eg. \f3SIGINT\f1) of the last signal -that was received during the most recent call to \f3gl_get_line()\f1, -or \f3-1\f1 if no signals were received. -.sp -On systems that support it, when a SIGWINCH (window change) signal is -received, \f3gl_get_line()\f1 queries the terminal to find out its new -size, redraws the current input line to accomodate the new size, then -returns to waiting for keyboard input from the user. Unlike other -signals, this signal isn't resent to the application. -.sp -Finally, the following signals cause \f3gl_get_line()\f1 to first -restore the terminal and signal environment to that which prevailed -before \f3gl_get_line()\f1 was called, then resend the signal to the -application. If the process still exists after the signal has been -delivered, then \f3gl_get_line()\f1 then re-establishes its own signal -handlers, switches the terminal back to raw mode, redisplays the input -line, and goes back to awaiting terminal input from the user. -.sp -.nf - SIGCONT - This signal is generated when a suspended - process is resumed. - - SIGPWR - This signal is generated when a power failure - occurs (presumably when the system is on a - UPS). - - SIGALRM - This signal is generated when a timer - expires. - - SIGUSR1 - An application specific signal. - - SIGUSR2 - Another application specific signal. - - SIGVTALRM - This signal is generated when a virtual - timer expires (see man setitimer(2)). - - SIGXCPU - This signal is generated when a process - exceeds its soft CPU time limit. - - SIGTSTP - This signal is generated by the terminal - suspend key, which is usually ^Z, or the - delayed terminal suspend key, which is - usually ^Y. - - SIGTTIN - This signal is generated if the program - attempts to read from the terminal while the - program is running in the background. - - SIGTTOU - This signal is generated if the program - attempts to write to the terminal while the - program is running in the background. -.fi -.sp - -Obviously not all of the above signals are supported on all systems, -so code to support them is conditionally compiled into the tecla -library. -.sp -Note that if \f3SIGKILL\f1, which by definition can't be caught, or -any of the hardware generated exception signals, such as -\f3SIGSEGV\f1, \f3SIGBUS\f1 and \f3SIGFPE\f1, are received and -unhandled while \f3gl_get_line()\f1 has the terminal in raw mode, the -program will be terminated without the terminal having been restored -to a usable state. In practice, job-control shells usually reset the -terminal settings when a process relinquishes the controlling -terminal, so this is only a problem with older shells. - -.SH CUSTOMIZED SIGNAL HANDLING - -The previous section listed the signals that -\f3gl_get_line()\f1 traps by default, and described how it -responds to them. This section describes how to both add and -remove signals from the list of trapped signals, and how to -specify how \f3gl_get_line()\f1 should respond to a given -signal. -.sp -If you don't need \f3gl_get_line()\f1 to do anything in -response to a signal that it normally traps, you can tell to -\f3gl_get_line()\f1 to ignore that signal by calling -\f3gl_ignore_signal()\f1. -.sp -.nf - int gl_ignore_signal(GetLine *gl, int signo); -.fi -.sp -The \f3signo\f1 argument is the number of the signal -(eg. \f3SIGINT\f1) that you want to have ignored. If the -specified signal isn't currently one of those being trapped, -this function does nothing. -.sp -The \f3gl_trap_signal()\f1 function allows you to either add -a new signal to the list that \f3gl_get_line()\f1 traps, or -modify how it responds to a signal that it already traps. -.sp -.nf - int gl_trap_signal(GetLine *gl, int signo, unsigned flags, - GlAfterSignal after, int errno_value); -.fi -.sp -The \f3signo\f1 argument is the number of the signal that -you wish to have trapped. The \f3flags\f1 argument is a set -of flags which determine the environment in which the -application's signal handler is invoked, the \f3after\f1 -argument tells \f3gl_get_line()\f1 what to do after the -application's signal handler returns, and \f3errno_value\f1 -tells \f3gl_get_line()\f1 what to set \f3errno\f1 to if told -to abort. -.sp -The \f3flags\f1 argument is a bitwise OR of zero or more of -the following enumerators: -.sp -.nf - GLS_RESTORE_SIG - Restore the caller's signal - environment while handling the - signal. - - GLS_RESTORE_TTY - Restore the caller's terminal settings - while handling the signal. - - GLS_RESTORE_LINE - Move the cursor to the start of the - line following the input line before - invoking the application's signal - handler. - - GLS_REDRAW_LINE - Redraw the input line when the - application's signal handler returns. - - GLS_UNBLOCK_SIG - Normally, if the calling program has - a signal blocked (man sigprocmask), - gl_get_line() does not trap that - signal. This flag tells gl_get_line() - to trap the signal and unblock it for - the duration of the call to - gl_get_line(). - - GLS_DONT_FORWARD - If this flag is included, the signal - will not be forwarded to the signal - handler of the calling program. -.fi -.sp -Two commonly useful flag combinations are also enumerated as -follows: -.sp -.nf - GLS_RESTORE_ENV = GLS_RESTORE_SIG | GLS_RESTORE_TTY | - GLS_REDRAW_LINE - - GLS_SUSPEND_INPUT = GLS_RESTORE_ENV | GLS_RESTORE_LINE -.fi -.sp - -If your signal handler, or the default system signal -handler for this signal, if you haven't overriden it, never -either writes to the terminal, nor suspends or terminates -the calling program, then you can safely set the \f3flags\f1 -argument to \f30\f1. -.sp -If your signal handler always writes to the terminal, reads -from it, or suspends or terminates the program, you should -specify the \f3flags\f1 argument as \f3GL_SUSPEND_INPUT\f1, -so that: -.sp -.nf -1. The cursor doesn't get left in the middle of the input - line. -2. So that the user can type in input and have it echoed. -3. So that you don't need to end each output line with - \f3\\r\\n\f1, instead of just \f3\\n\f1. -.fi -.sp -The \f3GL_RESTORE_ENV\f1 combination is the same as -\f3GL_SUSPEND_INPUT\f1, except that it doesn't move the -cursor, and if your signal handler doesn't read or write -anything to the terminal, the user won't see any visible -indication that a signal was caught. This can be useful if -you have a signal handler that only occasionally writes to -the terminal, where using \f3GL_SUSPEND_LINE\f1 would cause -the input line to be unnecessarily duplicated when nothing -had been written to the terminal. Such a signal handler, -when it does write to the terminal, should be sure to start -a new line at the start of its first write, by writing a -'\\n' character, and should be sure to leave the cursor on a -new line before returning. If the signal arrives while the -user is entering a line that only occupies a signal terminal -line, or if the cursor is on the last terminal line of a -longer input line, this will have the same effect as -\f3GL_SUSPEND_INPUT\f1. Otherwise it will start writing on a -line that already contains part of the displayed input line. -This doesn't do any harm, but it looks a bit ugly, which is -why the \f3GL_SUSPEND_INPUT\f1 combination is better if you -know that you are always going to be writting to the -terminal. -.sp -The \f3after\f1 argument, which determines what -\f3gl_get_line()\f1 does after the application's signal -handler returns (if it returns), can take any one of the -following values: -.sp -.nf - GLS_RETURN - Return the completed input line, just as - though the user had pressed the return - key. - - GLS_ABORT - Cause gl_get_line() to return \f3NULL\f1. - - GLS_CONTINUE - Resume command line editing. -.fi -.sp -The \f3errno_value\f1 argument is intended to be combined -with the \f3GLS_ABORT\f1 option, telling \f3gl_get_line()\f1 -what to set the standard \f3errno\f1 variable to before -returning \f3NULL\f1 to the calling program. It can also, -however, be used with the \f3GL_RETURN\f1 option, in case -you wish to have a way to distinguish between an input line -that was entered using the return key, and one that was -entered by the receipt of a signal. - -.SH THE TERMINAL SIZE - -On most systems the combination of the \f3TIOCGWINSZ\f1 ioctl and the -\f3SIGWINCH\f1 signal is used to maintain an accurate idea of the -terminal size. The terminal size is newly queried every time that -\f3gl_get_line()\f1 is called and whenever a \f3SIGWINCH\f1 signal is -received. -.sp -On the few systems where this mechanism isn't available, at -startup \f3new_GetLine()\f1 first looks for the \f3LINES\f1 -and \f3COLUMNS\f1 environment variables. If these aren't -found, or they contain unusable values, then if a terminal -information database like terminfo or termcap is available, -the default size of the terminal is looked up in this -database. If this too fails to provide the terminal size, a -default size of 80 columns by 24 lines is used. If this -default isn't appropriate for your system, -\f3gl_terminal_size()\f1 can be used to supply a different -fallback. -.sp -The \f3gl_terminal_size()\f1 function allows you to query -the current size of the terminal, and install an alternate -fallback size for cases where the size isn't available. -Beware that the terminal size won't be available if reading -from a pipe or a file, so the default values can be -important even on systems that do support ways of finding -out the terminal size. -.sp -.nf - typedef struct { - int nline; /* The terminal has nline lines */ - int ncolumn; /* The terminal has ncolumn columns */ - } GlTerminalSize; - - GlTerminalSize gl_terminal_size(GetLine *gl, - int def_ncolumn, - int def_nline); -.fi -.sp -This function first updates \f3gl_get_line()\f1's idea of -the terminal size, then records its findings in the return -value. -.sp -The \f3def_ncolumn\f1 and \f3def_nline\f1 specify the -default number of terminal columns and lines to use if the -terminal size can't be determined. - -.SH HIDING WHAT YOU TYPE - -When entering sensitive information, such as passwords, it is best not -to have the text that you are entering echoed on the terminal. -Furthermore, such text should not be recorded in the history list, -since somebody finding your terminal unattended could then recall it, -or somebody snooping through your directories could see it in your -history file. With this in mind, the \f3gl_echo_mode()\f1 -function allows you to toggle on and off the display and archival of -any text that is subsequently entered in calls to \f3gl_get_line()\f1. - -.sp -.nf - int gl_echo_mode(GetLine *gl, int enable); -.fi -.sp - -The \f3enable\f1 argument specifies whether entered text -should be visible or not. If it is \f30\f1, then -subsequently entered lines will not be visible on the -terminal, and will not be recorded in the history list. If -it is \f31\f1, then subsequent input lines will be displayed -as they are entered, and provided that history hasn't been -turned off via a call to \f3gl_toggle_history()\f1, then -they will also be archived in the history list. Finally, if -the \f3enable\f1 argument is \f3-1\f1, then the echoing mode -is left unchanged, which allows you to non-destructively -query the current setting via the return value. In all -cases, the return value of the function is \f30\f1 if -echoing was disabled before the function was called, and -\f31\f1 if it was enabled. -.sp -When echoing is turned off, note that although tab -completion will invisibly complete your prefix as far as -possible, ambiguous completions will not be displayed. - -.SH CALLBACK FUNCTION FACILITIES - -Unless otherwise stated, callback functions, such as tab -completion callbacks and event callbacks should not call any -functions in this module. The following functions, however, -are designed specifically to be used by callback functions. -.sp -Calling the \f3gl_replace_prompt()\f1 function from a -callback tells \f3gl_get_line() to display a different -prompt when the callback returns. It has no effect if called -when \f3gl_get_line()\f1 is not being called. -.sp -.nf - void gl_replace_prompt(GetLine *gl, const char *prompt); -.fi -.sp - -.SH INTERNATIONAL CHARACTER SETS - -Since libtecla version 1.4.0, \f3gl_get_line()\f1 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 -.nf - setlocale(LC_CTYPE, ""); -.fi -.sp -then the current locale is determined by the first of the environment -variables \f3LC_CTYPE\f1, \f3LC_ALL\f1, and \f3LANG\f1, that is found -to contain a valid locale name. If none of these variables are -defined, or the program neglects to call setlocale, then the default -\f3C\f1 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 -.nf - locale -a -.fi -.sp -at the shell prompt. -.sp -.SS "Meta keys and locales" - -Beware that in most locales other than the default C locale, meta -characters become printable, and they are then no longer considered to -match \f3M-c\f1 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 -\f3M-c\f1 can also be invoked by pressing the escape key momentarily, -then pressing the \f3c\f1 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 -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 -\f3EightBitInput\f1 X resource to \f3False\f1. You can either do this -by placing a line like the following in your \f3~/.Xdefaults\f1 file, -.sp -.nf - XTerm*EightBitInput: False -.sp -.fi -or by starting an xterm with an \f3-xrm '*EightBitInput: False'\f1 -command-line argument. In recent versions of xterm you can toggle this -feature on and off with the \f3"Meta Sends Escape"\f1 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 \f3Dtterm*KshMode\f1 resource to \f3True\f1. -.sp -.SS "Entering international characters" - -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 my PC the \f3xev\f1 program reports that pressing this -key generates keycode 115, so to turn this key into a compose key, I -do the following: -.sp -.nf - xmodmap -e 'keycode 115 = Multi_key' -.fi -.sp -I can then enter an i with a umlaut over it by typing this key, -followed by \f3"\f1, followed by i. - -.SH THREAD SAFETY - -In a multi-threaded program, you should use the libtecla_r.a version -of the library. This uses reentrant versions of system functions, -where available. Unfortunately neither terminfo nor termcap were -designed to be reentrant, so you can't safely use the functions of the -getline module in multiple threads (you can use the separate -file-expansion and word-completion modules in multiple threads, see -the corresponding man pages for details). However due to the use of -POSIX reentrant functions for looking up home directories etc, it is -safe to use this module from a single thread of a multi-threaded -program, provided that your other threads don't use any termcap or -terminfo functions. - -.SH FILES -.nf -libtecla.a - The tecla library -libtecla.h - The tecla header file. -~/.teclarc - The personal tecla customization file. -.fi - -.SH SEE ALSO -libtecla(3), ef_expand_file(3), cpl_complete_word(3), pca_lookup_file(3) - -.SH AUTHOR -Martin Shepherd (mcs@astro.caltech.edu) |