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diff --git a/doc/after.n b/doc/after.n new file mode 100644 index 0000000..cf4aaeb --- /dev/null +++ b/doc/after.n @@ -0,0 +1,109 @@ +'\" +'\" Copyright (c) 1990-1994 The Regents of the University of California. +'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +'\" SCCS: @(#) after.n 1.4 96/03/25 20:09:33 +'\" +.so man.macros +.TH after n 7.5 Tcl "Tcl Built-In Commands" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +after \- Execute a command after a time delay +.SH SYNOPSIS +\fBafter \fIms\fR +.sp +\fBafter \fIms \fR?\fIscript script script ...\fR? +.sp +\fBafter cancel \fIid\fR +.sp +\fBafter cancel \fIscript script script ...\fR +.sp +\fBafter idle \fR?\fIscript script script ...\fR? +.sp +\fBafter info \fR?\fIid\fR? +.BE + +.SH DESCRIPTION +.PP +This command is used to delay execution of the program or to execute +a command in background sometime in the future. It has several forms, +depending on the first argument to the command: +.TP +\fBafter \fIms\fR +\fIMs\fR must be an integer giving a time in milliseconds. +The command sleeps for \fIms\fR milliseconds and then returns. +While the command is sleeping the application does not respond to +events. +.TP +\fBafter \fIms \fR?\fIscript script script ...\fR? +In this form the command returns immediately, but it arranges +for a Tcl command to be executed \fIms\fR milliseconds later as an +event handler. +The command will be executed exactly once, at the given time. +The delayed command is formed by concatenating all the \fIscript\fR +arguments in the same fashion as the \fBconcat\fR command. +The command will be executed at global level (outside the context +of any Tcl procedure). +If an error occurs while executing the delayed command then the +\fBbgerror\fR mechanism is used to report the error. +The \fBafter\fR command returns an identifier that can be used +to cancel the delayed command using \fBafter cancel\fR. +.TP +\fBafter cancel \fIid\fR +Cancels the execution of a delayed command that +was previously scheduled. +\fIId\fR indicates which command should be canceled; it must have +been the return value from a previous \fBafter\fR command. +If the command given by \fIid\fR has already been executed then +the \fBafter cancel\fR command has no effect. +.TP +\fBafter cancel \fIscript script ...\fR +This command also cancels the execution of a delayed command. +The \fIscript\fR arguments are concatenated together with space +separators (just as in the \fBconcat\fR command). +If there is a pending command that matches the string, it is +cancelled and will never be executed; if no such command is +currently pending then the \fBafter cancel\fR command has no effect. +.TP +\fBafter idle \fIscript \fR?\fIscript script ...\fR? +Concatenates the \fIscript\fR arguments together with space +separators (just as in the \fBconcat\fR command), and arranges +for the resulting script to be evaluated later as an idle callback. +The script will be run exactly once, the next time the event +loop is entered and there are no events to process. +The command returns an identifier that can be used +to cancel the delayed command using \fBafter cancel\fR. +If an error occurs while executing the script then the +\fBbgerror\fR mechanism is used to report the error. +.TP +\fBafter info \fR?\fIid\fR? +This command returns information about existing event handlers. +If no \fIid\fR argument is supplied, the command returns +a list of the identifiers for all existing +event handlers created by the \fBafter\fR command for this +interpreter. +If \fIid\fR is supplied, it specifies an existing handler; +\fIid\fR must have been the return value from some previous call +to \fBafter\fR and it must not have triggered yet or been cancelled. +In this case the command returns a list with two elements. +The first element of the list is the script associated +with \fIid\fR, and the second element is either +\fBidle\fR or \fBtimer\fR to indicate what kind of event +handler it is. +.LP +The \fBafter \fIms\fR and \fBafter idle\fR forms of the command +assume that the application is event driven: the delayed commands +will not be executed unless the application enters the event loop. +In applications that are not normally event-driven, such as +\fBtclsh\fR, the event loop can be entered with the \fBvwait\fR +and \fBupdate\fR commands. + +.SH "SEE ALSO" +bgerror + +.SH KEYWORDS +cancel, delay, idle callback, sleep, time |