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diff --git a/readline-4.3.orig/doc/history.info b/readline-4.3.orig/doc/history.info new file mode 100644 index 0000000..98c0002 --- /dev/null +++ b/readline-4.3.orig/doc/history.info @@ -0,0 +1,840 @@ +This is history.info, produced by makeinfo version 4.1 from +/usr/homes/chet/src/bash/readline-src/doc/hist.texinfo. + +INFO-DIR-SECTION Libraries +START-INFO-DIR-ENTRY +* History: (history). The GNU history library API +END-INFO-DIR-ENTRY + + This document describes the GNU History library, a programming tool +that provides a consistent user interface for recalling lines of +previously typed input. + + Copyright (C) 1988-2002 Free Software Foundation, Inc. + + Permission is granted to make and distribute verbatim copies of this +manual provided the copyright notice and this permission notice pare +preserved on all copies. + + Permission is granted to copy and distribute modified versions of +this manual under the conditions for verbatim copying, provided that +the entire resulting derived work is distributed under the terms of a +permission notice identical to this one. + + Permission is granted to copy and distribute translations of this +manual into another language, under the above conditions for modified +versions, except that this permission notice may be stated in a +translation approved by the Free Software Foundation. + + +File: history.info, Node: Top, Next: Using History Interactively, Up: (dir) + +GNU History Library +******************* + + This document describes the GNU History library, a programming tool +that provides a consistent user interface for recalling lines of +previously typed input. + +* Menu: + +* Using History Interactively:: GNU History User's Manual. +* Programming with GNU History:: GNU History Programmer's Manual. +* Concept Index:: Index of concepts described in this manual. +* Function and Variable Index:: Index of externally visible functions + and variables. + + +File: history.info, Node: Using History Interactively, Next: Programming with GNU History, Prev: Top, Up: Top + +Using History Interactively +*************************** + + This chapter describes how to use the GNU History Library +interactively, from a user's standpoint. It should be considered a +user's guide. For information on using the GNU History Library in your +own programs, *note Programming with GNU History::. + +* Menu: + +* History Interaction:: What it feels like using History as a user. + + +File: history.info, Node: History Interaction, Up: Using History Interactively + +History Expansion +================= + + The History library provides a history expansion feature that is +similar to the history expansion provided by `csh'. This section +describes the syntax used to manipulate the history information. + + History expansions introduce words from the history list into the +input stream, making it easy to repeat commands, insert the arguments +to a previous command into the current input line, or fix errors in +previous commands quickly. + + History expansion takes place in two parts. The first is to +determine which line from the history list should be used during +substitution. The second is to select portions of that line for +inclusion into the current one. The line selected from the history is +called the "event", and the portions of that line that are acted upon +are called "words". Various "modifiers" are available to manipulate +the selected words. The line is broken into words in the same fashion +that Bash does, so that several words surrounded by quotes are +considered one word. History expansions are introduced by the +appearance of the history expansion character, which is `!' by default. + +* Menu: + +* Event Designators:: How to specify which history line to use. +* Word Designators:: Specifying which words are of interest. +* Modifiers:: Modifying the results of substitution. + + +File: history.info, Node: Event Designators, Next: Word Designators, Up: History Interaction + +Event Designators +----------------- + + An event designator is a reference to a command line entry in the +history list. + +`!' + Start a history substitution, except when followed by a space, tab, + the end of the line, `=' or `('. + +`!N' + Refer to command line N. + +`!-N' + Refer to the command N lines back. + +`!!' + Refer to the previous command. This is a synonym for `!-1'. + +`!STRING' + Refer to the most recent command starting with STRING. + +`!?STRING[?]' + Refer to the most recent command containing STRING. The trailing + `?' may be omitted if the STRING is followed immediately by a + newline. + +`^STRING1^STRING2^' + Quick Substitution. Repeat the last command, replacing STRING1 + with STRING2. Equivalent to `!!:s/STRING1/STRING2/'. + +`!#' + The entire command line typed so far. + + +File: history.info, Node: Word Designators, Next: Modifiers, Prev: Event Designators, Up: History Interaction + +Word Designators +---------------- + + Word designators are used to select desired words from the event. A +`:' separates the event specification from the word designator. It may +be omitted if the word designator begins with a `^', `$', `*', `-', or +`%'. Words are numbered from the beginning of the line, with the first +word being denoted by 0 (zero). Words are inserted into the current +line separated by single spaces. + + For example, + +`!!' + designates the preceding command. When you type this, the + preceding command is repeated in toto. + +`!!:$' + designates the last argument of the preceding command. This may be + shortened to `!$'. + +`!fi:2' + designates the second argument of the most recent command starting + with the letters `fi'. + + Here are the word designators: + +`0 (zero)' + The `0'th word. For many applications, this is the command word. + +`N' + The Nth word. + +`^' + The first argument; that is, word 1. + +`$' + The last argument. + +`%' + The word matched by the most recent `?STRING?' search. + +`X-Y' + A range of words; `-Y' abbreviates `0-Y'. + +`*' + All of the words, except the `0'th. This is a synonym for `1-$'. + It is not an error to use `*' if there is just one word in the + event; the empty string is returned in that case. + +`X*' + Abbreviates `X-$' + +`X-' + Abbreviates `X-$' like `X*', but omits the last word. + + If a word designator is supplied without an event specification, the +previous command is used as the event. + + +File: history.info, Node: Modifiers, Prev: Word Designators, Up: History Interaction + +Modifiers +--------- + + After the optional word designator, you can add a sequence of one or +more of the following modifiers, each preceded by a `:'. + +`h' + Remove a trailing pathname component, leaving only the head. + +`t' + Remove all leading pathname components, leaving the tail. + +`r' + Remove a trailing suffix of the form `.SUFFIX', leaving the + basename. + +`e' + Remove all but the trailing suffix. + +`p' + Print the new command but do not execute it. + +`s/OLD/NEW/' + Substitute NEW for the first occurrence of OLD in the event line. + Any delimiter may be used in place of `/'. The delimiter may be + quoted in OLD and NEW with a single backslash. If `&' appears in + NEW, it is replaced by OLD. A single backslash will quote the + `&'. The final delimiter is optional if it is the last character + on the input line. + +`&' + Repeat the previous substitution. + +`g' + Cause changes to be applied over the entire event line. Used in + conjunction with `s', as in `gs/OLD/NEW/', or with `&'. + + +File: history.info, Node: Programming with GNU History, Next: Concept Index, Prev: Using History Interactively, Up: Top + +Programming with GNU History +**************************** + + This chapter describes how to interface programs that you write with +the GNU History Library. It should be considered a technical guide. +For information on the interactive use of GNU History, *note Using +History Interactively::. + +* Menu: + +* Introduction to History:: What is the GNU History library for? +* History Storage:: How information is stored. +* History Functions:: Functions that you can use. +* History Variables:: Variables that control behaviour. +* History Programming Example:: Example of using the GNU History Library. + + +File: history.info, Node: Introduction to History, Next: History Storage, Up: Programming with GNU History + +Introduction to History +======================= + + Many programs read input from the user a line at a time. The GNU +History library is able to keep track of those lines, associate +arbitrary data with each line, and utilize information from previous +lines in composing new ones. + + The programmer using the History library has available functions for +remembering lines on a history list, associating arbitrary data with a +line, removing lines from the list, searching through the list for a +line containing an arbitrary text string, and referencing any line in +the list directly. In addition, a history "expansion" function is +available which provides for a consistent user interface across +different programs. + + The user using programs written with the History library has the +benefit of a consistent user interface with a set of well-known +commands for manipulating the text of previous lines and using that text +in new commands. The basic history manipulation commands are similar to +the history substitution provided by `csh'. + + If the programmer desires, he can use the Readline library, which +includes some history manipulation by default, and has the added +advantage of command line editing. + + Before declaring any functions using any functionality the History +library provides in other code, an application writer should include +the file `<readline/history.h>' in any file that uses the History +library's features. It supplies extern declarations for all of the +library's public functions and variables, and declares all of the +public data structures. + + +File: history.info, Node: History Storage, Next: History Functions, Prev: Introduction to History, Up: Programming with GNU History + +History Storage +=============== + + The history list is an array of history entries. A history entry is +declared as follows: + + typedef void *histdata_t; + + typedef struct _hist_entry { + char *line; + histdata_t data; + } HIST_ENTRY; + + The history list itself might therefore be declared as + + HIST_ENTRY **the_history_list; + + The state of the History library is encapsulated into a single +structure: + + /* + * A structure used to pass around the current state of the history. + */ + typedef struct _hist_state { + HIST_ENTRY **entries; /* Pointer to the entries themselves. */ + int offset; /* The location pointer within this array. */ + int length; /* Number of elements within this array. */ + int size; /* Number of slots allocated to this array. */ + int flags; + } HISTORY_STATE; + + If the flags member includes `HS_STIFLED', the history has been +stifled. + + +File: history.info, Node: History Functions, Next: History Variables, Prev: History Storage, Up: Programming with GNU History + +History Functions +================= + + This section describes the calling sequence for the various functions +exported by the GNU History library. + +* Menu: + +* Initializing History and State Management:: Functions to call when you + want to use history in a + program. +* History List Management:: Functions used to manage the list + of history entries. +* Information About the History List:: Functions returning information about + the history list. +* Moving Around the History List:: Functions used to change the position + in the history list. +* Searching the History List:: Functions to search the history list + for entries containing a string. +* Managing the History File:: Functions that read and write a file + containing the history list. +* History Expansion:: Functions to perform csh-like history + expansion. + + +File: history.info, Node: Initializing History and State Management, Next: History List Management, Up: History Functions + +Initializing History and State Management +----------------------------------------- + + This section describes functions used to initialize and manage the +state of the History library when you want to use the history functions +in your program. + + - Function: void using_history (void) + Begin a session in which the history functions might be used. This + initializes the interactive variables. + + - Function: HISTORY_STATE * history_get_history_state (void) + Return a structure describing the current state of the input + history. + + - Function: void history_set_history_state (HISTORY_STATE *state) + Set the state of the history list according to STATE. + + +File: history.info, Node: History List Management, Next: Information About the History List, Prev: Initializing History and State Management, Up: History Functions + +History List Management +----------------------- + + These functions manage individual entries on the history list, or set +parameters managing the list itself. + + - Function: void add_history (const char *string) + Place STRING at the end of the history list. The associated data + field (if any) is set to `NULL'. + + - Function: HIST_ENTRY * remove_history (int which) + Remove history entry at offset WHICH from the history. The + removed element is returned so you can free the line, data, and + containing structure. + + - Function: HIST_ENTRY * replace_history_entry (int which, const char + *line, histdata_t data) + Make the history entry at offset WHICH have LINE and DATA. This + returns the old entry so you can dispose of the data. In the case + of an invalid WHICH, a `NULL' pointer is returned. + + - Function: void clear_history (void) + Clear the history list by deleting all the entries. + + - Function: void stifle_history (int max) + Stifle the history list, remembering only the last MAX entries. + + - Function: int unstifle_history (void) + Stop stifling the history. This returns the previously-set + maximum number of history entries (as set by `stifle_history()'). + The value is positive if the history was stifled, negative if it + wasn't. + + - Function: int history_is_stifled (void) + Returns non-zero if the history is stifled, zero if it is not. + + +File: history.info, Node: Information About the History List, Next: Moving Around the History List, Prev: History List Management, Up: History Functions + +Information About the History List +---------------------------------- + + These functions return information about the entire history list or +individual list entries. + + - Function: HIST_ENTRY ** history_list (void) + Return a `NULL' terminated array of `HIST_ENTRY *' which is the + current input history. Element 0 of this list is the beginning of + time. If there is no history, return `NULL'. + + - Function: int where_history (void) + Returns the offset of the current history element. + + - Function: HIST_ENTRY * current_history (void) + Return the history entry at the current position, as determined by + `where_history()'. If there is no entry there, return a `NULL' + pointer. + + - Function: HIST_ENTRY * history_get (int offset) + Return the history entry at position OFFSET, starting from + `history_base' (*note History Variables::). If there is no entry + there, or if OFFSET is greater than the history length, return a + `NULL' pointer. + + - Function: int history_total_bytes (void) + Return the number of bytes that the primary history entries are + using. This function returns the sum of the lengths of all the + lines in the history. + + +File: history.info, Node: Moving Around the History List, Next: Searching the History List, Prev: Information About the History List, Up: History Functions + +Moving Around the History List +------------------------------ + + These functions allow the current index into the history list to be +set or changed. + + - Function: int history_set_pos (int pos) + Set the current history offset to POS, an absolute index into the + list. Returns 1 on success, 0 if POS is less than zero or greater + than the number of history entries. + + - Function: HIST_ENTRY * previous_history (void) + Back up the current history offset to the previous history entry, + and return a pointer to that entry. If there is no previous + entry, return a `NULL' pointer. + + - Function: HIST_ENTRY * next_history (void) + Move the current history offset forward to the next history entry, + and return the a pointer to that entry. If there is no next + entry, return a `NULL' pointer. + + +File: history.info, Node: Searching the History List, Next: Managing the History File, Prev: Moving Around the History List, Up: History Functions + +Searching the History List +-------------------------- + + These functions allow searching of the history list for entries +containing a specific string. Searching may be performed both forward +and backward from the current history position. The search may be +"anchored", meaning that the string must match at the beginning of the +history entry. + + - Function: int history_search (const char *string, int direction) + Search the history for STRING, starting at the current history + offset. If DIRECTION is less than 0, then the search is through + previous entries, otherwise through subsequent entries. If STRING + is found, then the current history index is set to that history + entry, and the value returned is the offset in the line of the + entry where STRING was found. Otherwise, nothing is changed, and + a -1 is returned. + + - Function: int history_search_prefix (const char *string, int + direction) + Search the history for STRING, starting at the current history + offset. The search is anchored: matching lines must begin with + STRING. If DIRECTION is less than 0, then the search is through + previous entries, otherwise through subsequent entries. If STRING + is found, then the current history index is set to that entry, and + the return value is 0. Otherwise, nothing is changed, and a -1 is + returned. + + - Function: int history_search_pos (const char *string, int direction, + int pos) + Search for STRING in the history list, starting at POS, an + absolute index into the list. If DIRECTION is negative, the search + proceeds backward from POS, otherwise forward. Returns the + absolute index of the history element where STRING was found, or + -1 otherwise. + + +File: history.info, Node: Managing the History File, Next: History Expansion, Prev: Searching the History List, Up: History Functions + +Managing the History File +------------------------- + + The History library can read the history from and write it to a file. +This section documents the functions for managing a history file. + + - Function: int read_history (const char *filename) + Add the contents of FILENAME to the history list, a line at a time. + If FILENAME is `NULL', then read from `~/.history'. Returns 0 if + successful, or `errno' if not. + + - Function: int read_history_range (const char *filename, int from, + int to) + Read a range of lines from FILENAME, adding them to the history + list. Start reading at line FROM and end at TO. If FROM is zero, + start at the beginning. If TO is less than FROM, then read until + the end of the file. If FILENAME is `NULL', then read from + `~/.history'. Returns 0 if successful, or `errno' if not. + + - Function: int write_history (const char *filename) + Write the current history to FILENAME, overwriting FILENAME if + necessary. If FILENAME is `NULL', then write the history list to + `~/.history'. Returns 0 on success, or `errno' on a read or write + error. + + - Function: int append_history (int nelements, const char *filename) + Append the last NELEMENTS of the history list to FILENAME. If + FILENAME is `NULL', then append to `~/.history'. Returns 0 on + success, or `errno' on a read or write error. + + - Function: int history_truncate_file (const char *filename, int + nlines) + Truncate the history file FILENAME, leaving only the last NLINES + lines. If FILENAME is `NULL', then `~/.history' is truncated. + Returns 0 on success, or `errno' on failure. + + +File: history.info, Node: History Expansion, Prev: Managing the History File, Up: History Functions + +History Expansion +----------------- + + These functions implement history expansion. + + - Function: int history_expand (char *string, char **output) + Expand STRING, placing the result into OUTPUT, a pointer to a + string (*note History Interaction::). Returns: + `0' + If no expansions took place (or, if the only change in the + text was the removal of escape characters preceding the + history expansion character); + + `1' + if expansions did take place; + + `-1' + if there was an error in expansion; + + `2' + if the returned line should be displayed, but not executed, + as with the `:p' modifier (*note Modifiers::). + + If an error ocurred in expansion, then OUTPUT contains a + descriptive error message. + + - Function: char * get_history_event (const char *string, int *cindex, + int qchar) + Returns the text of the history event beginning at STRING + + *CINDEX. *CINDEX is modified to point to after the event + specifier. At function entry, CINDEX points to the index into + STRING where the history event specification begins. QCHAR is a + character that is allowed to end the event specification in + addition to the "normal" terminating characters. + + - Function: char ** history_tokenize (const char *string) + Return an array of tokens parsed out of STRING, much as the shell + might. The tokens are split on the characters in the + HISTORY_WORD_DELIMITERS variable, and shell quoting conventions + are obeyed. + + - Function: char * history_arg_extract (int first, int last, const + char *string) + Extract a string segment consisting of the FIRST through LAST + arguments present in STRING. Arguments are split using + `history_tokenize'. + + +File: history.info, Node: History Variables, Next: History Programming Example, Prev: History Functions, Up: Programming with GNU History + +History Variables +================= + + This section describes the externally-visible variables exported by +the GNU History Library. + + - Variable: int history_base + The logical offset of the first entry in the history list. + + - Variable: int history_length + The number of entries currently stored in the history list. + + - Variable: int history_max_entries + The maximum number of history entries. This must be changed using + `stifle_history()'. + + - Variable: char history_expansion_char + The character that introduces a history event. The default is `!'. + Setting this to 0 inhibits history expansion. + + - Variable: char history_subst_char + The character that invokes word substitution if found at the start + of a line. The default is `^'. + + - Variable: char history_comment_char + During tokenization, if this character is seen as the first + character of a word, then it and all subsequent characters up to a + newline are ignored, suppressing history expansion for the + remainder of the line. This is disabled by default. + + - Variable: char * history_word_delimiters + The characters that separate tokens for `history_tokenize()'. The + default value is `" \t\n()<>;&|"'. + + - Variable: char * history_no_expand_chars + The list of characters which inhibit history expansion if found + immediately following HISTORY_EXPANSION_CHAR. The default is + space, tab, newline, carriage return, and `='. + + - Variable: char * history_search_delimiter_chars + The list of additional characters which can delimit a history + search string, in addition to space, TAB, `:' and `?' in the case + of a substring search. The default is empty. + + - Variable: int history_quotes_inhibit_expansion + If non-zero, single-quoted words are not scanned for the history + expansion character. The default value is 0. + + - Variable: rl_linebuf_func_t * history_inhibit_expansion_function + This should be set to the address of a function that takes two + arguments: a `char *' (STRING) and an `int' index into that string + (I). It should return a non-zero value if the history expansion + starting at STRING[I] should not be performed; zero if the + expansion should be done. It is intended for use by applications + like Bash that use the history expansion character for additional + purposes. By default, this variable is set to `NULL'. + + +File: history.info, Node: History Programming Example, Prev: History Variables, Up: Programming with GNU History + +History Programming Example +=========================== + + The following program demonstrates simple use of the GNU History +Library. + + #include <stdio.h> + #include <readline/history.h> + + main (argc, argv) + int argc; + char **argv; + { + char line[1024], *t; + int len, done = 0; + + line[0] = 0; + + using_history (); + while (!done) + { + printf ("history$ "); + fflush (stdout); + t = fgets (line, sizeof (line) - 1, stdin); + if (t && *t) + { + len = strlen (t); + if (t[len - 1] == '\n') + t[len - 1] = '\0'; + } + + if (!t) + strcpy (line, "quit"); + + if (line[0]) + { + char *expansion; + int result; + + result = history_expand (line, &expansion); + if (result) + fprintf (stderr, "%s\n", expansion); + + if (result < 0 || result == 2) + { + free (expansion); + continue; + } + + add_history (expansion); + strncpy (line, expansion, sizeof (line) - 1); + free (expansion); + } + + if (strcmp (line, "quit") == 0) + done = 1; + else if (strcmp (line, "save") == 0) + write_history ("history_file"); + else if (strcmp (line, "read") == 0) + read_history ("history_file"); + else if (strcmp (line, "list") == 0) + { + register HIST_ENTRY **the_list; + register int i; + + the_list = history_list (); + if (the_list) + for (i = 0; the_list[i]; i++) + printf ("%d: %s\n", i + history_base, the_list[i]->line); + } + else if (strncmp (line, "delete", 6) == 0) + { + int which; + if ((sscanf (line + 6, "%d", &which)) == 1) + { + HIST_ENTRY *entry = remove_history (which); + if (!entry) + fprintf (stderr, "No such entry %d\n", which); + else + { + free (entry->line); + free (entry); + } + } + else + { + fprintf (stderr, "non-numeric arg given to `delete'\n"); + } + } + } + } + + +File: history.info, Node: Concept Index, Next: Function and Variable Index, Prev: Programming with GNU History, Up: Top + +Concept Index +************* + +* Menu: + +* anchored search: Searching the History List. +* event designators: Event Designators. +* history events: Event Designators. +* history expansion: History Interaction. +* History Searching: Searching the History List. + + +File: history.info, Node: Function and Variable Index, Prev: Concept Index, Up: Top + +Function and Variable Index +*************************** + +* Menu: + +* add_history: History List Management. +* append_history: Managing the History File. +* clear_history: History List Management. +* current_history: Information About the History List. +* get_history_event: History Expansion. +* history_arg_extract: History Expansion. +* history_base: History Variables. +* history_comment_char: History Variables. +* history_expand: History Expansion. +* history_expansion_char: History Variables. +* history_get: Information About the History List. +* history_get_history_state: Initializing History and State Management. +* history_inhibit_expansion_function: History Variables. +* history_is_stifled: History List Management. +* history_length: History Variables. +* history_list: Information About the History List. +* history_max_entries: History Variables. +* history_no_expand_chars: History Variables. +* history_quotes_inhibit_expansion: History Variables. +* history_search: Searching the History List. +* history_search_delimiter_chars: History Variables. +* history_search_pos: Searching the History List. +* history_search_prefix: Searching the History List. +* history_set_history_state: Initializing History and State Management. +* history_set_pos: Moving Around the History List. +* history_subst_char: History Variables. +* history_tokenize: History Expansion. +* history_total_bytes: Information About the History List. +* history_truncate_file: Managing the History File. +* history_word_delimiters: History Variables. +* next_history: Moving Around the History List. +* previous_history: Moving Around the History List. +* read_history: Managing the History File. +* read_history_range: Managing the History File. +* remove_history: History List Management. +* replace_history_entry: History List Management. +* stifle_history: History List Management. +* unstifle_history: History List Management. +* using_history: Initializing History and State Management. +* where_history: Information About the History List. +* write_history: Managing the History File. + + + +Tag Table: +Node: Top1136 +Node: Using History Interactively1716 +Node: History Interaction2223 +Node: Event Designators3642 +Node: Word Designators4569 +Node: Modifiers6198 +Node: Programming with GNU History7336 +Node: Introduction to History8061 +Node: History Storage9746 +Node: History Functions10857 +Node: Initializing History and State Management11841 +Node: History List Management12641 +Node: Information About the History List14235 +Node: Moving Around the History List15591 +Node: Searching the History List16580 +Node: Managing the History File18498 +Node: History Expansion20304 +Node: History Variables22199 +Node: History Programming Example24766 +Node: Concept Index27488 +Node: Function and Variable Index27974 + +End Tag Table |