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Diffstat (limited to 'tcl/doc/update.n')
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diff --git a/tcl/doc/update.n b/tcl/doc/update.n new file mode 100644 index 00000000000..27484e4d6d8 --- /dev/null +++ b/tcl/doc/update.n @@ -0,0 +1,48 @@ +'\" +'\" Copyright (c) 1990-1992 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. +'\" +'\" RCS: @(#) $Id$ +'\" +.so man.macros +.TH update n 7.5 Tcl "Tcl Built-In Commands" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +update \- Process pending events and idle callbacks +.SH SYNOPSIS +\fBupdate\fR ?\fBidletasks\fR? +.BE + +.SH DESCRIPTION +.PP +This command is used to bring the application ``up to date'' +by entering the event loop repeated until all pending events +(including idle callbacks) have been processed. +.PP +If the \fBidletasks\fR keyword is specified as an argument to the +command, then no new events or errors are processed; only idle +callbacks are invoked. +This causes operations that are normally deferred, such as display +updates and window layout calculations, to be performed immediately. +.PP +The \fBupdate idletasks\fR command is useful in scripts where +changes have been made to the application's state and you want those +changes to appear on the display immediately, rather than waiting +for the script to complete. Most display updates are performed as +idle callbacks, so \fBupdate idletasks\fR will cause them to run. +However, there are some kinds of updates that only happen in +response to events, such as those triggered by window size changes; +these updates will not occur in \fBupdate idletasks\fR. +.PP +The \fBupdate\fR command with no options is useful in scripts where +you are performing a long-running computation but you still want +the application to respond to events such as user interactions; if +you occasionally call \fBupdate\fR then user input will be processed +during the next call to \fBupdate\fR. + +.SH KEYWORDS +event, flush, handler, idle, update |