[ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ] 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.
 
history.html#SEC11. Using History Interactively   GNU History User's Manual. history.html#SEC62. Programming with GNU History   GNU History Programmer's Manual. history.html#SEC19A. Copying This Manual   history.html#SEC22B. Concept Index   Index of concepts described in this manual. history.html#SEC23C. Function and Variable Index   Index of externally visible functions
				  and variables.
[ history.html#SEC_Top < ] [ history.html#SEC2 > ]    [ << ] [ history.html#SEC_Top Up ] [ history.html#SEC6 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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,
see section 
history.html#SEC62. Programming with GNU History .
 
history.html#SEC21.1 History Expansion   What it feels like using History as a user. [ history.html#SEC1 < ] [ history.html#SEC3 > ]    [ << ] [ history.html#SEC1 Up ] [ history.html#SEC6 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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.
 
history.html#SEC31.1.1 Event Designators   How to specify which history line to use. history.html#SEC41.1.2 Word Designators   Specifying which words are of interest. history.html#SEC51.1.3 Modifiers   Modifying the results of substitution. [ history.html#SEC2 < ] [ history.html#SEC4 > ]    [ << ] [ history.html#SEC2 Up ] [ history.html#SEC6 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  1.1.1 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 
`='.
!nRefer to command line n.
!-nRefer to the command n lines back.
!!Refer to the previous command.  This is a synonym for `!-1'.
!stringRefer 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 string1with 
string2.  Equivalent to
!!:s/string1/string2/.
!#The entire command line typed so far.
[ history.html#SEC3 < ] [ history.html#SEC5 > ]    [ history.html#SEC5 << ] [ history.html#SEC2 Up ] [ history.html#SEC6 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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:2designates the second argument of the most recent command starting with
the letters 
fi.
Here are the word designators:
 
0 (zero)The 0th word.  For many applications, this is the command word.
nThe nth word.
^The first argument; that is, word 1.
$The last argument.
%The word matched by the most recent `?string?' search.
x-yA range of words; `-y' abbreviates `0-y'.
*All of the words, except the 0th.  This is a synonym for `1-$'.
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.
[ history.html#SEC4 < ] [ history.html#SEC6 > ]    [ << ] [ history.html#SEC2 Up ] [ history.html#SEC6 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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 
`:'.
hRemove a trailing pathname component, leaving only the head.
tRemove all leading  pathname  components, leaving the tail.
rRemove a trailing suffix of the form `.suffix', leaving
the basename.
eRemove all but the trailing suffix.
pPrint 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 newwith 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.
gaCause changes to be applied over the entire event line.  Used in
conjunction with 
`s', as in gs/old/new/,
or with 
`&'.
GApply the following `s' modifier once to each word in the event.
[ history.html#SEC5 < ] [ history.html#SEC7 > ]    [ << ] [ history.html#SEC_Top Up ] [ history.html#SEC19 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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, see section 
history.html#SEC11. Using History Interactively .
 
history.html#SEC72.1 Introduction to History   What is the GNU History library for? history.html#SEC82.2 History Storage   How information is stored. history.html#SEC92.3 History Functions   Functions that you can use. history.html#SEC172.4 History Variables   Variables that control behaviour. history.html#SEC182.5 History Programming Example   Example of using the GNU History Library. [ history.html#SEC6 < ] [ history.html#SEC8 > ]    [ << ] [ history.html#SEC6 Up ] [ history.html#SEC19 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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.
[ history.html#SEC7 < ] [ history.html#SEC9 > ]    [ history.html#SEC9 << ] [ history.html#SEC6 Up ] [ history.html#SEC19 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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.
[ history.html#SEC8 < ] [ history.html#SEC10 > ]    [ history.html#SEC17 << ] [ history.html#SEC6 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  2.3 History Functions 
This section describes the calling sequence for the various functions
exported by the GNU History library.
 
history.html#SEC102.3.1 Initializing History and State Management   Functions to call when you
						want to use history in a
						program.
history.html#SEC112.3.2 History List Management   Functions used to manage the list
					of history entries.
history.html#SEC122.3.3 Information About the History List   Functions returning information about
					the history list.
history.html#SEC132.3.4 Moving Around the History List   Functions used to change the position
					in the history list.
history.html#SEC142.3.5 Searching the History List   Functions to search the history list
					for entries containing a string.
history.html#SEC152.3.6 Managing the History File   Functions that read and write a file
					containing the history list.
history.html#SEC162.3.7 History Expansion   Functions to perform csh-like history
					expansion.
[ history.html#SEC9 < ] [ history.html#SEC11 > ]    [ history.html#SEC17 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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.
[ history.html#SEC10 < ] [ history.html#SEC12 > ]    [ history.html#SEC12 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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.
[ history.html#SEC11 < ] [ history.html#SEC13 > ]    [ history.html#SEC13 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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 NULLpointer.
Function: HIST_ENTRY * history_get (int offset)Return the history entry at position offset, starting from
history_base (see section history.html#SEC172.4 History Variables ).
If there is no entry there, or if 
offsetis 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.
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.
[ history.html#SEC12 < ] [ history.html#SEC14 > ]    [ history.html#SEC14 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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)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.
[ history.html#SEC13 < ] [ history.html#SEC15 > ]    [ history.html#SEC15 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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.
[ history.html#SEC14 < ] [ history.html#SEC16 > ]    [ history.html#SEC16 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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 filenameif 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.
[ history.html#SEC15 < ] [ history.html#SEC17 > ]    [ history.html#SEC17 << ] [ history.html#SEC9 Up ] [ history.html#SEC17 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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 (see section 
history.html#SEC21.1 History Expansion ).  Returns:
0If no expansions took place (or, if the only change in
the text was the removal of escape characters preceding the history expansion
character);
1if expansions did take place;
-1if there was an error in expansion;
2if the returned line should be displayed, but not executed,
as with the 
:p modifier (see section history.html#SEC51.1.3 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.  qcharis 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 lastarguments present in 
string.  Arguments are split using
history_tokenize.
[ history.html#SEC16 < ] [ history.html#SEC18 > ]    [ history.html#SEC18 << ] [ history.html#SEC6 Up ] [ history.html#SEC19 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  2.4 History Variables 
This section describes the externally-visible variables exported by
the GNU History Library.
Variable: int history_baseThe logical offset of the first entry in the history list.
Variable: int history_lengthThe number of entries currently stored in the history list.
Variable: int history_max_entriesThe maximum number of history entries.  This must be changed using
stifle_history().
Variable: int history_write_timestampsIf 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.
Variable: char history_expansion_charThe character that introduces a history event.  The default is `!'.
Setting this to 0 inhibits history expansion.
Variable: char history_subst_charThe character that invokes word substitution if found at the start of
a line.  The default is 
`^'.
Variable: char history_comment_charDuring 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_delimitersThe characters that separate tokens for history_tokenize().
The default value is 
" \t\n();&|".
Variable: char * history_search_delimiter_charsThe 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_charsThe 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_expansionIf 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_functionThis 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.
[ history.html#SEC17 < ] [ history.html#SEC19 > ]    [ << ] [ history.html#SEC6 Up ] [ history.html#SEC19 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  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");
            }
        }
    }
}
[ history.html#SEC18 < ] [ history.html#SEC20 > ]    [ history.html#SEC6 << ] [ history.html#SEC_Top Up ] [ history.html#SEC22 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  A. Copying This Manual 
 
history.html#SEC20A.1 GNU Free Documentation License   License for copying this manual. [ history.html#SEC19 < ] [ history.html#SEC21 > ]    [ history.html#SEC19 << ] [ history.html#SEC19 Up ] [ history.html#SEC22 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  A.1 GNU Free Documentation License 
 Version 1.2, November 2002
 Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA  02111-1307, USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
PREAMBLE
The purpose of this License is to make a manual, textbook, or other
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We have designed this License in order to use it for manuals for free
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VERBATIM COPYING
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COPYING IN QUANTITY
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It is requested, but not required, that you contact the authors of the
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MODIFICATIONS
You may copy and distribute a Modified Version of the Document under
the conditions of sections 2 and 3 above, provided that you release
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Use in the Title Page (and on the covers, if any) a title distinct
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(which should, if there were any, be listed in the History section
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if the original publisher of that version gives permission.
List on the Title Page, as authors, one or more persons or entities
responsible for authorship of the modifications in the Modified
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Document (all of its principal authors, if it has fewer than five),
unless they release you from this requirement.
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Preserve all the copyright notices of the Document.
Add an appropriate copyright notice for your modifications
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Include, immediately after the copyright notices, a license notice
giving the public permission to use the Modified Version under the
terms of this License, in the form shown in the Addendum below.
Preserve in that license notice the full lists of Invariant Sections
and required Cover Texts given in the Document's license notice.
Include an unaltered copy of this License.
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to it an item stating at least the title, year, new authors, and
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it was based on.  These may be placed in the "History" section.
You may omit a network location for a work that was published at
least four years before the Document itself, or if the original
publisher of the version it refers to gives permission.
For any section Entitled "Acknowledgements" or "Dedications", Preserve
the Title of the section, and preserve in the section all the
substance and tone of each of the contributor acknowledgements and/or
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or the equivalent are not considered part of the section titles.
Delete any section Entitled "Endorsements".  Such a section
may not be included in the Modified Version.
Do not retitle any existing section to be Entitled "Endorsements" or
to conflict in title with any Invariant Section.
Preserve any Warranty Disclaimers.
If the Modified Version includes new front-matter sections or
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of these sections as invariant.  To do this, add their titles to the
list of Invariant Sections in the Modified Version's license notice.
These titles must be distinct from any other section titles.
You may add a section Entitled "Endorsements", provided it contains
nothing but endorsements of your Modified Version by various
parties--for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of a
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You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list
of Cover Texts in the Modified Version.  Only one passage of
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The author(s) and publisher(s) of the Document do not by this License
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COMBINING DOCUMENTS
You may combine the Document with other documents released under this
License, under the terms defined in section 4 above for modified
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list them all as Invariant Sections of your combined work in its
license notice, and that you preserve all their Warranty Disclaimers.
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adding at the end of it, in parentheses, the name of the original
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Make the same adjustment to the section titles in the list of
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In the combination, you must combine any sections Entitled "History"
in the various original documents, forming one section Entitled
"History"; likewise combine any sections Entitled "Acknowledgements",
and any sections Entitled "Dedications".  You must delete all
sections Entitled "Endorsements."
COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other documents
released under this License, and replace the individual copies of this
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verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute
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other respects regarding verbatim copying of that document.
AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other separate
and independent documents or works, in or on a volume of a storage or
distribution medium, is called an "aggregate" if the copyright
resulting from the compilation is not used to limit the legal rights
of the compilation's users beyond what the individual works permit.
When the Document is included an aggregate, this License does not
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If the Cover Text requirement of section 3 is applicable to these
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TRANSLATION
Translation is considered a kind of modification, so you may
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Replacing Invariant Sections with translations requires special
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of those notices and disclaimers.  In case of a disagreement between
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or disclaimer, the original version will prevail.
If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to Preserve
its Title (section 1) will typically require changing the actual
title.
TERMINATION
You may not copy, modify, sublicense, or distribute the Document except
as expressly provided for under this License.  Any other attempt to
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automatically terminate your rights under this License.  However,
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FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions
of the GNU Free Documentation License from time to time.  Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns.  See
http://www.gnu.org/copyleft/http://www.gnu.org/copyleft/ .
Each version of the License is given a distinguishing version number.
If the Document specifies that a particular numbered version of this
License "or any later version" applies to it, you have the option of
following the terms and conditions either of that specified version or
of any later version that has been published (not as a draft) by the
Free Software Foundation.  If the Document does not specify a version
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as a draft) by the Free Software Foundation.
[ history.html#SEC20 < ] [ history.html#SEC22 > ]    [ history.html#SEC19 << ] [ history.html#SEC20 Up ] [ history.html#SEC22 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  A.1.1 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 1.2
  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.
[ history.html#SEC21 < ] [ history.html#SEC23 > ]    [ history.html#SEC23 << ] [ history.html#SEC_Top Up ] [ history.html#SEC23 >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  B. Concept Index 
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Index Entry Section  A history.html#IDX23anchored search history.html#SEC142.3.5 Searching the History List  E history.html#SEC3event designators history.html#SEC31.1.1 Event Designators  F history.html#IDX48FDL, GNU Free Documentation License history.html#SEC20A.1 GNU Free Documentation License  H history.html#IDX1history events history.html#SEC31.1.1 Event Designators history.html#SEC2history expansion history.html#SEC21.1 History Expansion history.html#SEC14History Searching history.html#SEC142.3.5 Searching the History List  
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[ history.html#SEC22 < ] [ > ]    [ << ] [ history.html#SEC_Top Up ] [ >> ]             [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ]  C. Function and Variable Index 
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Index Entry Section  A history.html#IDX5add_history history.html#SEC112.3.2 History List Management history.html#IDX6add_history_time history.html#SEC112.3.2 History List Management history.html#IDX30append_history history.html#SEC152.3.6 Managing the History File  C history.html#IDX10clear_history history.html#SEC112.3.2 History List Management history.html#IDX16current_history history.html#SEC122.3.3 Information About the History List  F history.html#IDX8free_history_entry history.html#SEC112.3.2 History List Management  G history.html#IDX33get_history_event history.html#SEC162.3.7 History Expansion  H history.html#IDX35history_arg_extract history.html#SEC162.3.7 History Expansion history.html#IDX36history_base history.html#SEC172.4 History Variables history.html#IDX42history_comment_char history.html#SEC172.4 History Variables history.html#IDX32history_expand history.html#SEC162.3.7 History Expansion history.html#IDX40history_expansion_char history.html#SEC172.4 History Variables history.html#IDX17history_get history.html#SEC122.3.3 Information About the History List history.html#IDX3history_get_history_state history.html#SEC102.3.1 Initializing History and State Management history.html#IDX18history_get_time history.html#SEC122.3.3 Information About the History List history.html#IDX47history_inhibit_expansion_function history.html#SEC172.4 History Variables history.html#IDX13history_is_stifled history.html#SEC112.3.2 History List Management history.html#IDX37history_length history.html#SEC172.4 History Variables history.html#IDX14history_list history.html#SEC122.3.3 Information About the History List history.html#IDX38history_max_entries history.html#SEC172.4 History Variables history.html#IDX45history_no_expand_chars history.html#SEC172.4 History Variables history.html#IDX46history_quotes_inhibit_expansion history.html#SEC172.4 History Variables history.html#IDX24history_search history.html#SEC142.3.5 Searching the History List history.html#IDX44history_search_delimiter_chars history.html#SEC172.4 History Variables history.html#IDX26history_search_pos history.html#SEC142.3.5 Searching the History List history.html#IDX25history_search_prefix history.html#SEC142.3.5 Searching the History List history.html#IDX4history_set_history_state history.html#SEC102.3.1 Initializing History and State Management history.html#IDX20history_set_pos history.html#SEC132.3.4 Moving Around the History List history.html#IDX41history_subst_char history.html#SEC172.4 History Variables history.html#IDX34history_tokenize history.html#SEC162.3.7 History Expansion history.html#IDX19history_total_bytes history.html#SEC122.3.3 Information About the History List history.html#IDX31history_truncate_file history.html#SEC152.3.6 Managing the History File history.html#IDX43history_word_delimiters history.html#SEC172.4 History Variables history.html#IDX39history_write_timestamps history.html#SEC172.4 History Variables  N history.html#IDX22next_history history.html#SEC132.3.4 Moving Around the History List  P history.html#IDX21previous_history history.html#SEC132.3.4 Moving Around the History List  R history.html#IDX27read_history history.html#SEC152.3.6 Managing the History File history.html#IDX28read_history_range history.html#SEC152.3.6 Managing the History File history.html#IDX7remove_history history.html#SEC112.3.2 History List Management history.html#IDX9replace_history_entry history.html#SEC112.3.2 History List Management  S history.html#IDX11stifle_history history.html#SEC112.3.2 History List Management  U history.html#IDX12unstifle_history history.html#SEC112.3.2 History List Management history.html#IDX2using_history history.html#SEC102.3.1 Initializing History and State Management  W history.html#IDX15where_history history.html#SEC122.3.3 Information About the History List history.html#IDX29write_history history.html#SEC152.3.6 Managing the History File  
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[ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ] Table of Contents
history.html#SEC11. Using History Interactively history.html#SEC21.1 History Expansion history.html#SEC31.1.1 Event Designators history.html#SEC41.1.2 Word Designators history.html#SEC51.1.3 Modifiers history.html#SEC62. Programming with GNU History history.html#SEC72.1 Introduction to History history.html#SEC82.2 History Storage history.html#SEC92.3 History Functions history.html#SEC102.3.1 Initializing History and State Management history.html#SEC112.3.2 History List Management history.html#SEC122.3.3 Information About the History List history.html#SEC132.3.4 Moving Around the History List history.html#SEC142.3.5 Searching the History List history.html#SEC152.3.6 Managing the History File history.html#SEC162.3.7 History Expansion history.html#SEC172.4 History Variables history.html#SEC182.5 History Programming Example history.html#SEC19A. Copying This Manual history.html#SEC20A.1 GNU Free Documentation License history.html#SEC21A.1.1 ADDENDUM: How to use this License for your documents history.html#SEC22B. Concept Index history.html#SEC23C. Function and Variable Index [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ] Short Table of Contents
history.html#SEC11. Using History Interactively history.html#SEC62. Programming with GNU History history.html#SEC19A. Copying This Manual history.html#SEC22B. Concept Index history.html#SEC23C. Function and Variable Index [ history.html#SEC_TopTop ] [ history.html#SEC_ContentsContents ] [ history.html#SEC22Index ] [ history.html#SEC_About ? ] About this document
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