103 lines
4.1 KiB
Plaintext
103 lines
4.1 KiB
Plaintext
|
'\"
|
||
|
|
'\" Copyright (c) 1993 The Regents of the University of California.
|
||
|
|
'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
|
||
|
|
'\"
|
||
|
|
'\" See the file "license.terms" for information on usage and redistribution
|
||
|
|
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||
|
|
'\"
|
||
|
|
.TH history n "" Tcl "Tcl Built-In Commands"
|
||
|
|
.so man.macros
|
||
|
|
.BS
|
||
|
|
'\" Note: do not modify the .SH NAME line immediately below!
|
||
|
|
.SH NAME
|
||
|
|
history \- Manipulate the history list
|
||
|
|
.SH SYNOPSIS
|
||
|
|
\fBhistory \fR?\fIoption\fR? ?\fIarg arg ...\fR?
|
||
|
|
.BE
|
||
|
|
.SH DESCRIPTION
|
||
|
|
.PP
|
||
|
|
The \fBhistory\fR command performs one of several operations related to
|
||
|
|
recently-executed commands recorded in a history list. Each of
|
||
|
|
these recorded commands is referred to as an
|
||
|
|
.QW event .
|
||
|
|
When specifying an event to the \fBhistory\fR command, the following
|
||
|
|
forms may be used:
|
||
|
|
.IP [1]
|
||
|
|
A number: if positive, it refers to the event with
|
||
|
|
that number (all events are numbered starting at 1). If the number
|
||
|
|
is negative, it selects an event relative to the current event
|
||
|
|
(\fB\-1\fR refers to the previous event, \fB\-2\fR to the one before that, and
|
||
|
|
so on). Event \fB0\fR refers to the current event.
|
||
|
|
.IP [2]
|
||
|
|
A string: selects the most recent event that matches the string.
|
||
|
|
An event is considered to match the string either if the string is
|
||
|
|
the same as the first characters of the event, or if the string
|
||
|
|
matches the event in the sense of the \fBstring match\fR command.
|
||
|
|
.PP
|
||
|
|
The \fBhistory\fR command can take any of the following forms:
|
||
|
|
.TP
|
||
|
|
\fBhistory\fR
|
||
|
|
Same
|
||
|
|
as \fBhistory info\fR, described below.
|
||
|
|
.TP
|
||
|
|
\fBhistory add\fI command \fR?\fBexec\fR?
|
||
|
|
Adds the \fIcommand\fR argument to the history list as a new event. If
|
||
|
|
\fBexec\fR is specified (or abbreviated) then the command is also
|
||
|
|
executed and its result is returned. If \fBexec\fR is not specified
|
||
|
|
then an empty string is returned as result.
|
||
|
|
.TP
|
||
|
|
\fBhistory change\fI newValue\fR ?\fIevent\fR?
|
||
|
|
Replaces the value recorded for an event with \fInewValue\fR. \fIEvent\fR
|
||
|
|
specifies the event to replace, and
|
||
|
|
defaults to the \fIcurrent\fR event (not event \fB\-1\fR). This command
|
||
|
|
is intended for use in commands that implement new forms of history
|
||
|
|
substitution and wish to replace the current event (which invokes the
|
||
|
|
substitution) with the command created through substitution. The return
|
||
|
|
value is an empty string.
|
||
|
|
.TP
|
||
|
|
\fBhistory clear\fR
|
||
|
|
Erase the history list. The current keep limit is retained.
|
||
|
|
The history event numbers are reset.
|
||
|
|
.TP
|
||
|
|
\fBhistory event\fR ?\fIevent\fR?
|
||
|
|
Returns the value of the event given by \fIevent\fR. \fIEvent\fR
|
||
|
|
defaults to \fB\-1\fR.
|
||
|
|
.TP
|
||
|
|
\fBhistory info \fR?\fIcount\fR?
|
||
|
|
Returns a formatted string (intended for humans to read) giving
|
||
|
|
the event number and contents for each of the events in the history
|
||
|
|
list except the current event. If \fIcount\fR is specified
|
||
|
|
then only the most recent \fIcount\fR events are returned.
|
||
|
|
.TP
|
||
|
|
\fBhistory keep \fR?\fIcount\fR?
|
||
|
|
This command may be used to change the size of the history list to
|
||
|
|
\fIcount\fR events. Initially, 20 events are retained in the history
|
||
|
|
list. If \fIcount\fR is not specified, the current keep limit is returned.
|
||
|
|
.TP
|
||
|
|
\fBhistory nextid\fR
|
||
|
|
Returns the number of the next event to be recorded
|
||
|
|
in the history list. It is useful for things like printing the
|
||
|
|
event number in command-line prompts.
|
||
|
|
.TP
|
||
|
|
\fBhistory redo \fR?\fIevent\fR?
|
||
|
|
Re-executes the command indicated by \fIevent\fR and returns its result.
|
||
|
|
\fIEvent\fR defaults to \fB\-1\fR. This command results in history
|
||
|
|
revision: see below for details.
|
||
|
|
.SH "HISTORY REVISION"
|
||
|
|
.PP
|
||
|
|
Pre-8.0 Tcl had a complex history revision mechanism.
|
||
|
|
The current mechanism is more limited, and the old
|
||
|
|
history operations \fBsubstitute\fR and \fBwords\fR have been removed.
|
||
|
|
(As a consolation, the \fBclear\fR operation was added.)
|
||
|
|
.PP
|
||
|
|
The history option \fBredo\fR results in much simpler
|
||
|
|
.QW "history revision" .
|
||
|
|
When this option is invoked then the most recent event
|
||
|
|
is modified to eliminate the history command and replace it with
|
||
|
|
the result of the history command.
|
||
|
|
If you want to redo an event without modifying history, then use
|
||
|
|
the \fBevent\fR operation to retrieve some event,
|
||
|
|
and the \fBadd\fR operation to add it to history and execute it.
|
||
|
|
.SH KEYWORDS
|
||
|
|
event, history, record
|