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author | William Joye <wjoye@cfa.harvard.edu> | 2017-09-22 18:51:12 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2017-09-22 18:51:12 (GMT) |
commit | 3fa8e6dc88e8041b6cb88d1b1e9c05676d3346b7 (patch) | |
tree | 69afbb41089c8358615879f7cd3c4cf7997f4c7e /tcl8.6/doc/after.n | |
parent | a0e17db23c0fd7c771c0afce8cce350c98f90b02 (diff) | |
download | blt-3fa8e6dc88e8041b6cb88d1b1e9c05676d3346b7.zip blt-3fa8e6dc88e8041b6cb88d1b1e9c05676d3346b7.tar.gz blt-3fa8e6dc88e8041b6cb88d1b1e9c05676d3346b7.tar.bz2 |
update to tcl/tk 8.6.7
Diffstat (limited to 'tcl8.6/doc/after.n')
-rw-r--r-- | tcl8.6/doc/after.n | 151 |
1 files changed, 0 insertions, 151 deletions
diff --git a/tcl8.6/doc/after.n b/tcl8.6/doc/after.n deleted file mode 100644 index 3d0d2c4..0000000 --- a/tcl8.6/doc/after.n +++ /dev/null @@ -1,151 +0,0 @@ -'\" -'\" 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. -'\" -.TH after n 7.5 Tcl "Tcl Built-In Commands" -.so man.macros -.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 background error will be reported by the command -registered with \fBinterp bgerror\fR. -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 -canceled 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 -background error will be reported by the command -registered with \fBinterp bgerror\fR. -.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 canceled. -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 "EXAMPLES" -This defines a command to make Tcl do nothing at all for \fIN\fR -seconds: -.PP -.CS -proc sleep {N} { - \fBafter\fR [expr {int($N * 1000)}] -} -.CE -.PP -This arranges for the command \fIwake_up\fR to be run in eight hours -(providing the event loop is active at that time): -.PP -.CS -\fBafter\fR [expr {1000 * 60 * 60 * 8}] wake_up -.CE -.PP -The following command can be used to do long-running calculations (as -represented here by \fI::my_calc::one_step\fR, which is assumed to -return a boolean indicating whether another step should be performed) -in a step-by-step fashion, though the calculation itself needs to be -arranged so it can work step-wise. This technique is extra careful to -ensure that the event loop is not starved by the rescheduling of -processing steps (arranging for the next step to be done using an -already-triggered timer event only when the event queue has been -drained) and is useful when you want to ensure that a Tk GUI remains -responsive during a slow task. -.PP -.CS -proc doOneStep {} { - if {[::my_calc::one_step]} { - \fBafter idle\fR [list \fBafter\fR 0 doOneStep] - } -} -doOneStep -.CE -.SH "SEE ALSO" -concat(n), interp(n), update(n), vwait(n) -.SH KEYWORDS -cancel, delay, idle callback, sleep, time -'\" Local Variables: -'\" mode: nroff -'\" End: |