path: root/doc/history.info

This is history.info, produced by makeinfo version 6.1 from
history.texi.

This document describes the GNU History library (version 7.0, 16 July
2016), a programming tool that provides a consistent user interface for
recalling lines of previously typed input.

   Copyright (C) 1988-2016 Free Software Foundation, Inc.

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU Free Documentation License,
     Version 1.3 or any later version published by the Free Software
     Foundation; with no Invariant Sections, no Front-Cover Texts, and
     no Back-Cover Texts.  A copy of the license is included in the
     section entitled "GNU Free Documentation License".

INFO-DIR-SECTION Libraries
START-INFO-DIR-ENTRY
* History: (history).       The GNU history library API.
END-INFO-DIR-ENTRY


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.
* GNU Free Documentation License::	License for copying this 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

1 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

1.1 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

1.1.1 Event Designators
-----------------------

An event designator is a reference to a command line entry in the
history list.  Unless the reference is absolute, events are relative to
the current position 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 preceding the current position in
     the history list starting with STRING.

'!?STRING[?]'
     Refer to the most recent command preceding the current position in
     the history list 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

1.1.2 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

1.1.3 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'
'a'
     Cause changes to be applied over the entire event line.  Used in
     conjunction with 's', as in 'gs/OLD/NEW/', or with '&'.

'G'
     Apply the following 's' modifier once to each word in the event.


File: history.info,  Node: Programming with GNU History,  Next: GNU Free Documentation License,  Prev: Using History Interactively,  Up: Top

2 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

2.1 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

2.2 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;
       char *timestamp;
       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

2.3 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

2.3.1 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

2.3.2 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: void add_history_time (const char *string)
     Change the time stamp associated with the most recent history entry
     to STRING.

 -- 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: histdata_t free_history_entry (HIST_ENTRY *histent)
     Free the history entry HISTENT and any history library private data
     associated with it.  Returns the application-specific data so the
     caller can dispose of it.

 -- 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 the caller can dispose of any
     application-specific 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

2.3.3 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: time_t history_get_time (HIST_ENTRY *entry)
     Return the time stamp associated with the history entry ENTRY.  If
     the timestamp is missing or invalid, return 0.

 -- 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

2.3.4 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)
     If the current history offset refers to a valid history entry,
     increment the current history offset.  If the possibly-incremented
     history offset refers to a valid history entry, return a pointer to
     that entry; otherwise, return a 'BNULL' pointer.


File: history.info,  Node: Searching the History List,  Next: Managing the History File,  Prev: Moving Around the History List,  Up: History Functions

2.3.5 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

2.3.6 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

2.3.7 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 occurred 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

2.4 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: int history_write_timestamps
     If non-zero, timestamps are written to the history file, so they
     can be preserved between sessions.  The default value is 0, meaning
     that timestamps are not saved.

     The current timestamp format uses the value of HISTORY_COMMENT_CHAR
     to delimit timestamp entries in the history file.  If that variable
     does not have a value (the default), timestamps will not be
     written.

 -- 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_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: 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: int history_quotes_inhibit_expansion
     If non-zero, double-quoted words are not scanned for the history
     expansion character or the history comment 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

2.5 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: GNU Free Documentation License,  Next: Concept Index,  Prev: Programming with GNU History,  Up: Top

Appendix A GNU Free Documentation License
*****************************************

                     Version 1.3, 3 November 2008

     Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
     <http://fsf.org/>

     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

  0. PREAMBLE

     The purpose of this License is to make a manual, textbook, or other
     functional and useful document "free" in the sense of freedom: to
     assure everyone the effective freedom to copy and redistribute it,
     with or without modifying it, either commercially or
     noncommercially.  Secondarily, this License preserves for the
     author and publisher a way to get credit for their work, while not
     being considered responsible for modifications made by others.

     This License is a kind of "copyleft", which means that derivative
     works of the document must themselves be free in the same sense.
     It complements the GNU General Public License, which is a copyleft
     license designed for free software.

     We have designed this License in order to use it for manuals for
     free software, because free software needs free documentation: a
     free program should come with manuals providing the same freedoms
     that the software does.  But this License is not limited to
     software manuals; it can be used for any textual work, regardless
     of subject matter or whether it is published as a printed book.  We
     recommend this License principally for works whose purpose is
     instruction or reference.

  1. APPLICABILITY AND DEFINITIONS

     This License applies to any manual or other work, in any medium,
     that contains a notice placed by the copyright holder saying it can
     be distributed under the terms of this License.  Such a notice
     grants a world-wide, royalty-free license, unlimited in duration,
     to use that work under the conditions stated herein.  The
     "Document", below, refers to any such manual or work.  Any member
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  5. COMBINING DOCUMENTS

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  6. COLLECTIONS OF DOCUMENTS

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  7. AGGREGATION WITH INDEPENDENT WORKS

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  9. TERMINATION

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  10. FUTURE REVISIONS OF THIS LICENSE

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  11. RELICENSING

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     The operator of an MMC Site may republish an MMC contained in the
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ADDENDUM: How to use this License for your documents
====================================================

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:

       Copyright (C)  YEAR  YOUR NAME.
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3
       or any later version published by the Free Software Foundation;
       with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
       Texts.  A copy of the license is included in the section entitled ``GNU
       Free Documentation License''.

   If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the "with...Texts."  line with this:

         with the Invariant Sections being LIST THEIR TITLES, with
         the Front-Cover Texts being LIST, and with the Back-Cover Texts
         being LIST.

   If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

   If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of free
software license, such as the GNU General Public License, to permit
their use in free software.


File: history.info,  Node: Concept Index,  Next: Function and Variable Index,  Prev: GNU Free Documentation License,  Up: Top

Appendix B Concept Index
************************

[index]
* Menu:

* anchored search:                       Searching the History List.
                                                               (line 10)
* event designators:                     Event Designators.    (line  6)
* history events:                        Event Designators.    (line  8)
* history expansion:                     History Interaction.  (line  6)
* History Searching:                     Searching the History List.
                                                               (line  6)


File: history.info,  Node: Function and Variable Index,  Prev: Concept Index,  Up: Top

Appendix C Function and Variable Index
**************************************

[index]
* Menu:

* add_history:                           History List Management.
                                                               (line  9)
* add_history_time:                      History List Management.
                                                               (line 13)
* append_history:                        Managing the History File.
                                                               (line 28)
* clear_history:                         History List Management.
                                                               (line 34)
* current_history:                       Information About the History List.
                                                               (line 17)
* free_history_entry:                    History List Management.
                                                               (line 22)
* get_history_event:                     History Expansion.    (line 26)
* history_arg_extract:                   History Expansion.    (line 41)
* history_base:                          History Variables.    (line  9)
* history_comment_char:                  History Variables.    (line 37)
* history_expand:                        History Expansion.    (line  8)
* history_expansion_char:                History Variables.    (line 29)
* history_get:                           Information About the History List.
                                                               (line 22)
* history_get_history_state:             Initializing History and State Management.
                                                               (line 14)
* history_get_time:                      Information About the History List.
                                                               (line 28)
* history_inhibit_expansion_function:    History Variables.    (line 62)
* history_is_stifled:                    History List Management.
                                                               (line 46)
* history_length:                        History Variables.    (line 12)
* history_list:                          Information About the History List.
                                                               (line  9)
* history_max_entries:                   History Variables.    (line 15)
* history_no_expand_chars:               History Variables.    (line 52)
* history_quotes_inhibit_expansion:      History Variables.    (line 57)
* history_search:                        Searching the History List.
                                                               (line 12)
* history_search_delimiter_chars:        History Variables.    (line 47)
* history_search_pos:                    Searching the History List.
                                                               (line 31)
* history_search_prefix:                 Searching the History List.
                                                               (line 21)
* history_set_history_state:             Initializing History and State Management.
                                                               (line 18)
* history_set_pos:                       Moving Around the History List.
                                                               (line  9)
* history_subst_char:                    History Variables.    (line 33)
* history_tokenize:                      History Expansion.    (line 35)
* history_total_bytes:                   Information About the History List.
                                                               (line 32)
* history_truncate_file:                 Managing the History File.
                                                               (line 33)
* history_word_delimiters:               History Variables.    (line 43)
* history_write_timestamps:              History Variables.    (line 19)
* next_history:                          Moving Around the History List.
                                                               (line 19)
* previous_history:                      Moving Around the History List.
                                                               (line 14)
* read_history:                          Managing the History File.
                                                               (line  9)
* read_history_range:                    Managing the History File.
                                                               (line 14)
* remove_history:                        History List Management.
                                                               (line 17)
* replace_history_entry:                 History List Management.
                                                               (line 27)
* stifle_history:                        History List Management.
                                                               (line 37)
* unstifle_history:                      History List Management.
                                                               (line 40)
* using_history:                         Initializing History and State Management.
                                                               (line 10)
* where_history:                         Information About the History List.
                                                               (line 14)
* write_history:                         Managing the History File.
                                                               (line 22)



Tag Table:
Node: Top845
Node: Using History Interactively1490
Node: History Interaction1998
Node: Event Designators3422
Node: Word Designators4561
Node: Modifiers6198
Node: Programming with GNU History7421
Node: Introduction to History8165
Node: History Storage9855
Node: History Functions10990
Node: Initializing History and State Management11979
Node: History List Management12791
Node: Information About the History List14824
Node: Moving Around the History List16377
Node: Searching the History List17470
Node: Managing the History File19395
Node: History Expansion21215
Node: History Variables23125
Node: History Programming Example26195
Node: GNU Free Documentation License28872
Node: Concept Index54044
Node: Function and Variable Index54749

End Tag Table