439 lines
15 KiB
Plaintext
439 lines
15 KiB
Plaintext
@ignore
|
|
This file documents the user interface to the GNU History library.
|
|
|
|
Copyright (C) 1988-1999 Free Software Foundation, Inc.
|
|
Authored by Brian Fox and Chet Ramey.
|
|
|
|
Permission is granted to make and distribute verbatim copies of this manual
|
|
provided the copyright notice and this permission notice are preserved on
|
|
all copies.
|
|
|
|
Permission is granted to process this file through Tex and print the
|
|
results, provided the printed document carries copying permission notice
|
|
identical to this one except for the removal of this paragraph (this
|
|
paragraph not being relevant to the printed manual).
|
|
|
|
Permission is granted to copy and distribute modified versions of this
|
|
manual under the conditions for verbatim copying, provided also that the
|
|
GNU Copyright statement is available to the distributee, and 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.
|
|
@end ignore
|
|
|
|
@node Using History Interactively
|
|
@chapter Using History Interactively
|
|
|
|
@c @ifclear BashFeatures
|
|
@c @defcodeindex bt
|
|
@c @end ifclear
|
|
|
|
@ifset BashFeatures
|
|
This chapter describes how to use the @sc{gnu} History Library
|
|
interactively, from a user's standpoint.
|
|
It should be considered a user's guide.
|
|
For information on using the @sc{gnu} History Library in other programs,
|
|
see the @sc{gnu} Readline Library Manual.
|
|
@end ifset
|
|
@ifclear BashFeatures
|
|
This chapter describes how to use the GNU History Library interactively,
|
|
from a user's standpoint. It should be considered a user's guide.
|
|
@c For
|
|
@c information on using the GNU History Library in your own programs,
|
|
@c @pxref{Programming with GNU History}.
|
|
@end ifclear
|
|
|
|
@ifset BashFeatures
|
|
@menu
|
|
* Bash History Facilities:: How Bash lets you manipulate your command
|
|
history.
|
|
* Bash History Builtins:: The Bash builtin commands that manipulate
|
|
the command history.
|
|
* History Interaction:: What it feels like using History as a user.
|
|
@end menu
|
|
@end ifset
|
|
@ifclear BashFeatures
|
|
@menu
|
|
* History Interaction:: What it feels like using History as a user.
|
|
@end menu
|
|
@end ifclear
|
|
|
|
@ifset BashFeatures
|
|
@node Bash History Facilities
|
|
@section Bash History Facilities
|
|
@cindex command history
|
|
@cindex history list
|
|
|
|
When the @samp{-o history} option to the @code{set} builtin
|
|
is enabled (@pxref{The Set Builtin}),
|
|
the shell provides access to the @var{command history},
|
|
the list of commands previously typed.
|
|
The value of the @code{HISTSIZE} shell variable is used as the
|
|
number of commands to save in a history list.
|
|
The text of the last @code{$HISTSIZE}
|
|
commands (default 500) is saved.
|
|
The shell stores each command in the history list prior to
|
|
parameter and variable expansion
|
|
but after history expansion is performed, subject to the
|
|
values of the shell variables
|
|
@code{HISTIGNORE} and @code{HISTCONTROL}.
|
|
|
|
When the shell starts up, the history is initialized from the
|
|
file named by the @code{HISTFILE} variable (default @file{~/.bash_history}).
|
|
The file named by the value of @code{HISTFILE} is truncated, if
|
|
necessary, to contain no more than the number of lines specified by
|
|
the value of the @code{HISTFILESIZE} variable.
|
|
When an interactive shell exits, the last
|
|
@code{$HISTSIZE} lines are copied from the history list to the file
|
|
named by @code{$HISTFILE}.
|
|
If the @code{histappend} shell option is set (@pxref{Bash Builtins}),
|
|
the lines are appended to the history file,
|
|
otherwise the history file is overwritten.
|
|
If @code{HISTFILE}
|
|
is unset, or if the history file is unwritable, the history is
|
|
not saved. After saving the history, the history file is truncated
|
|
to contain no more than @code{$HISTFILESIZE}
|
|
lines. If @code{HISTFILESIZE} is not set, no truncation is performed.
|
|
|
|
The builtin command @code{fc} may be used to list or edit and re-execute
|
|
a portion of the history list.
|
|
The @code{history} builtin may be used to display or modify the history
|
|
list and manipulate the history file.
|
|
When using command-line editing, search commands
|
|
are available in each editing mode that provide access to the
|
|
history list (@pxref{Commands For History}).
|
|
|
|
The shell allows control over which commands are saved on the history
|
|
list. The @code{HISTCONTROL} and @code{HISTIGNORE}
|
|
variables may be set to cause the shell to save only a subset of the
|
|
commands entered.
|
|
The @code{cmdhist}
|
|
shell option, if enabled, causes the shell to attempt to save each
|
|
line of a multi-line command in the same history entry, adding
|
|
semicolons where necessary to preserve syntactic correctness.
|
|
The @code{lithist}
|
|
shell option causes the shell to save the command with embedded newlines
|
|
instead of semicolons.
|
|
The @code{shopt} builtin is used to set these options.
|
|
@xref{Bash Builtins}, for a description of @code{shopt}.
|
|
|
|
@node Bash History Builtins
|
|
@section Bash History Builtins
|
|
@cindex history builtins
|
|
|
|
Bash provides two builtin commands which manipulate the
|
|
history list and history file.
|
|
|
|
@table @code
|
|
|
|
@item fc
|
|
@btindex fc
|
|
@example
|
|
@code{fc [-e @var{ename}] [-nlr] [@var{first}] [@var{last}]}
|
|
@code{fc -s [@var{pat}=@var{rep}] [@var{command}]}
|
|
@end example
|
|
|
|
Fix Command. In the first form, a range of commands from @var{first} to
|
|
@var{last} is selected from the history list. Both @var{first} and
|
|
@var{last} may be specified as a string (to locate the most recent
|
|
command beginning with that string) or as a number (an index into the
|
|
history list, where a negative number is used as an offset from the
|
|
current command number). If @var{last} is not specified it is set to
|
|
@var{first}. If @var{first} is not specified it is set to the previous
|
|
command for editing and @minus{}16 for listing. If the @samp{-l} flag is
|
|
given, the commands are listed on standard output. The @samp{-n} flag
|
|
suppresses the command numbers when listing. The @samp{-r} flag
|
|
reverses the order of the listing. Otherwise, the editor given by
|
|
@var{ename} is invoked on a file containing those commands. If
|
|
@var{ename} is not given, the value of the following variable expansion
|
|
is used: @code{$@{FCEDIT:-$@{EDITOR:-vi@}@}}. This says to use the
|
|
value of the @code{FCEDIT} variable if set, or the value of the
|
|
@code{EDITOR} variable if that is set, or @code{vi} if neither is set.
|
|
When editing is complete, the edited commands are echoed and executed.
|
|
|
|
In the second form, @var{command} is re-executed after each instance
|
|
of @var{pat} in the selected command is replaced by @var{rep}.
|
|
|
|
A useful alias to use with the @code{fc} command is @code{r='fc -s'}, so
|
|
that typing @samp{r cc} runs the last command beginning with @code{cc}
|
|
and typing @samp{r} re-executes the last command (@pxref{Aliases}).
|
|
|
|
@item history
|
|
@btindex history
|
|
@example
|
|
history [@var{n}]
|
|
history -c
|
|
history -d @var{offset}
|
|
history [-anrw] [@var{filename}]
|
|
history -ps @var{arg}
|
|
@end example
|
|
|
|
With no options, display the history list with line numbers.
|
|
Lines prefixed with with a @samp{*} have been modified.
|
|
An argument of @var{n} lists only the last @var{n} lines.
|
|
Options, if supplied, have the following meanings:
|
|
|
|
@table @code
|
|
@item -c
|
|
Clear the history list. This may be combined
|
|
with the other options to replace the history list completely.
|
|
|
|
@item -d @var{offset}
|
|
Delete the history entry at position @var{offset}.
|
|
@var{offset} should be specified as it appears when the history is
|
|
displayed.
|
|
|
|
@item -a
|
|
Append the new
|
|
history lines (history lines entered since the beginning of the
|
|
current Bash session) to the history file.
|
|
|
|
@item -n
|
|
Append the history lines not already read from the history file
|
|
to the current history list. These are lines appended to the history
|
|
file since the beginning of the current Bash session.
|
|
|
|
@item -r
|
|
Read the current history file and append its contents to
|
|
the history list.
|
|
|
|
@item -w
|
|
Write out the current history to the history file.
|
|
|
|
@item -p
|
|
Perform history substitution on the @var{arg}s and display the result
|
|
on the standard output, without storing the results in the history list.
|
|
|
|
@item -s
|
|
The @var{arg}s are added to the end of
|
|
the history list as a single entry.
|
|
|
|
@end table
|
|
|
|
When any of the @samp{-w}, @samp{-r}, @samp{-a}, or @samp{-n} options is
|
|
used, if @var{filename}
|
|
is given, then it is used as the history file. If not, then
|
|
the value of the @code{HISTFILE} variable is used.
|
|
|
|
@end table
|
|
@end ifset
|
|
|
|
@node History Interaction
|
|
@section History Expansion
|
|
@cindex history expansion
|
|
|
|
The History library provides a history expansion feature that is similar
|
|
to the history expansion provided by @code{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
|
|
@dfn{event}, and the portions of that line that are acted upon are
|
|
called @dfn{words}. Various @dfn{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 @samp{!} by default.
|
|
@ifset BashFeatures
|
|
Only @samp{\} and @samp{'} may be used to escape the history expansion
|
|
character.
|
|
@end ifset
|
|
|
|
@ifset BashFeatures
|
|
Several shell options settable with the @code{shopt}
|
|
builtin (@pxref{Bash Builtins}) may be used to tailor
|
|
the behavior of history expansion. If the
|
|
@code{histverify} shell option is enabled, and Readline
|
|
is being used, history substitutions are not immediately passed to
|
|
the shell parser.
|
|
Instead, the expanded line is reloaded into the Readline
|
|
editing buffer for further modification.
|
|
If Readline is being used, and the @code{histreedit}
|
|
shell option is enabled, a failed history expansion will be
|
|
reloaded into the Readline editing buffer for correction.
|
|
The @samp{-p} option to the @code{history} builtin command
|
|
may be used to see what a history expansion will do before using it.
|
|
The @samp{-s} option to the @code{history} builtin may be used to
|
|
add commands to the end of the history list without actually executing
|
|
them, so that they are available for subsequent recall.
|
|
This is most useful in conjunction with Readline.
|
|
|
|
The shell allows control of the various characters used by the
|
|
history expansion mechanism with the @code{histchars} variable.
|
|
@end ifset
|
|
|
|
@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.
|
|
@end menu
|
|
|
|
@node Event Designators
|
|
@subsection Event Designators
|
|
@cindex event designators
|
|
|
|
An event designator is a reference to a command line entry in the
|
|
history list.
|
|
@cindex history events
|
|
|
|
@table @asis
|
|
|
|
@item @code{!}
|
|
Start a history substitution, except when followed by a space, tab,
|
|
the end of the line, @samp{=} or @samp{(}.
|
|
|
|
@item @code{!@var{n}}
|
|
Refer to command line @var{n}.
|
|
|
|
@item @code{!-@var{n}}
|
|
Refer to the command @var{n} lines back.
|
|
|
|
@item @code{!!}
|
|
Refer to the previous command. This is a synonym for @samp{!-1}.
|
|
|
|
@item @code{!@var{string}}
|
|
Refer to the most recent command starting with @var{string}.
|
|
|
|
@item @code{!?@var{string}[?]}
|
|
Refer to the most recent command containing @var{string}. The trailing
|
|
@samp{?} may be omitted if the @var{string} is followed immediately by
|
|
a newline.
|
|
|
|
@item @code{^@var{string1}^@var{string2}^}
|
|
Quick Substitution. Repeat the last command, replacing @var{string1}
|
|
with @var{string2}. Equivalent to
|
|
@code{!!:s/@var{string1}/@var{string2}/}.
|
|
|
|
@item @code{!#}
|
|
The entire command line typed so far.
|
|
|
|
@end table
|
|
|
|
@node Word Designators
|
|
@subsection Word Designators
|
|
|
|
Word designators are used to select desired words from the event.
|
|
A @samp{:} separates the event specification from the word designator. It
|
|
may be omitted if the word designator begins with a @samp{^}, @samp{$},
|
|
@samp{*}, @samp{-}, or @samp{%}. Words are numbered from the beginning
|
|
of the line, with the first word being denoted by 0 (zero). Words are
|
|
inserted into the current line separated by single spaces.
|
|
|
|
@need 0.75
|
|
For example,
|
|
|
|
@table @code
|
|
@item !!
|
|
designates the preceding command. When you type this, the preceding
|
|
command is repeated in toto.
|
|
|
|
@item !!:$
|
|
designates the last argument of the preceding command. This may be
|
|
shortened to @code{!$}.
|
|
|
|
@item !fi:2
|
|
designates the second argument of the most recent command starting with
|
|
the letters @code{fi}.
|
|
@end table
|
|
|
|
@need 0.75
|
|
Here are the word designators:
|
|
|
|
@table @code
|
|
|
|
@item 0 (zero)
|
|
The @code{0}th word. For many applications, this is the command word.
|
|
|
|
@item @var{n}
|
|
The @var{n}th word.
|
|
|
|
@item ^
|
|
The first argument; that is, word 1.
|
|
|
|
@item $
|
|
The last argument.
|
|
|
|
@item %
|
|
The word matched by the most recent @samp{?@var{string}?} search.
|
|
|
|
@item @var{x}-@var{y}
|
|
A range of words; @samp{-@var{y}} abbreviates @samp{0-@var{y}}.
|
|
|
|
@item *
|
|
All of the words, except the @code{0}th. This is a synonym for @samp{1-$}.
|
|
It is not an error to use @samp{*} if there is just one word in the event;
|
|
the empty string is returned in that case.
|
|
|
|
@item @var{x}*
|
|
Abbreviates @samp{@var{x}-$}
|
|
|
|
@item @var{x}-
|
|
Abbreviates @samp{@var{x}-$} like @samp{@var{x}*}, but omits the last word.
|
|
|
|
@end table
|
|
|
|
If a word designator is supplied without an event specification, the
|
|
previous command is used as the event.
|
|
|
|
@node Modifiers
|
|
@subsection Modifiers
|
|
|
|
After the optional word designator, you can add a sequence of one or more
|
|
of the following modifiers, each preceded by a @samp{:}.
|
|
|
|
@table @code
|
|
|
|
@item h
|
|
Remove a trailing pathname component, leaving only the head.
|
|
|
|
@item t
|
|
Remove all leading pathname components, leaving the tail.
|
|
|
|
@item r
|
|
Remove a trailing suffix of the form @samp{.@var{suffix}}, leaving
|
|
the basename.
|
|
|
|
@item e
|
|
Remove all but the trailing suffix.
|
|
|
|
@item p
|
|
Print the new command but do not execute it.
|
|
|
|
@ifset BashFeatures
|
|
@item q
|
|
Quote the substituted words, escaping further substitutions.
|
|
|
|
@item x
|
|
Quote the substituted words as with @samp{q},
|
|
but break into words at spaces, tabs, and newlines.
|
|
@end ifset
|
|
|
|
@item s/@var{old}/@var{new}/
|
|
Substitute @var{new} for the first occurrence of @var{old} in the
|
|
event line. Any delimiter may be used in place of @samp{/}.
|
|
The delimiter may be quoted in @var{old} and @var{new}
|
|
with a single backslash. If @samp{&} appears in @var{new},
|
|
it is replaced by @var{old}. A single backslash will quote
|
|
the @samp{&}. The final delimiter is optional if it is the last
|
|
character on the input line.
|
|
|
|
@item &
|
|
Repeat the previous substitution.
|
|
|
|
@item g
|
|
Cause changes to be applied over the entire event line. Used in
|
|
conjunction with @samp{s}, as in @code{gs/@var{old}/@var{new}/},
|
|
or with @samp{&}.
|
|
|
|
@end table
|