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diff --git a/doc/CrtTimerHdlr.3 b/doc/CrtTimerHdlr.3 new file mode 100644 index 0000000..14f48a4 --- /dev/null +++ b/doc/CrtTimerHdlr.3 @@ -0,0 +1,76 @@ +'\" +'\" Copyright (c) 1990 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: @(#) CrtTimerHdlr.3 1.4 96/09/17 10:54:58 +'\" +.so man.macros +.TH Tcl_CreateTimerHandler 3 7.5 Tcl "Tcl Library Procedures" +.BS +.SH NAME +Tcl_CreateTimerHandler, Tcl_DeleteTimerHandler \- call a procedure at a +given time +.SH SYNOPSIS +.nf +\fB#include <tcl.h>\fR +.sp +Tcl_TimerToken +\fBTcl_CreateTimerHandler\fR(\fImilliseconds, proc, clientData\fR) +.sp +\fBTcl_DeleteTimerHandler\fR(\fItoken\fR) +.SH ARGUMENTS +.AS Tcl_TimerToken milliseconds +.AP int milliseconds in +How many milliseconds to wait before invoking \fIproc\fR. +.AP Tcl_TimerProc *proc in +Procedure to invoke after \fImilliseconds\fR have elapsed. +.AP ClientData clientData in +Arbitrary one-word value to pass to \fIproc\fR. +.AP Tcl_TimerToken token in +Token for previously-created timer handler (the return value +from some previous call to \fBTcl_CreateTimerHandler\fR). +.BE + +.SH DESCRIPTION +.PP +\fBTcl_CreateTimerHandler\fR arranges for \fIproc\fR to be +invoked at a time \fImilliseconds\fR milliseconds in the +future. +The callback to \fIproc\fR will be made by \fBTcl_DoOneEvent\fR, +so \fBTcl_CreateTimerHandler\fR is only useful in programs that +dispatch events through \fBTcl_DoOneEvent\fR or through Tcl commands +such as \fBvwait\fR. +The call to \fIproc\fR may not be made at the exact time given by +\fImilliseconds\fR: it will be made at the next opportunity +after that time. For example, if \fBTcl_DoOneEvent\fR isn't +called until long after the time has elapsed, or if there +are other pending events to process before the call to +\fIproc\fR, then the call to \fIproc\fR will be delayed. +.PP +\fIProc\fR should have arguments and return value that match +the type \fBTcl_TimerProc\fR: +.CS +typedef void Tcl_TimerProc(ClientData \fIclientData\fR); +.CE +The \fIclientData\fR parameter to \fIproc\fR is a +copy of the \fIclientData\fR argument given to +\fBTcl_CreateTimerHandler\fR when the callback +was created. Typically, \fIclientData\fR points to a data +structure containing application-specific information about +what to do in \fIproc\fR. +.PP +\fBTcl_DeleteTimerHandler\fR may be called to delete a +previously-created timer handler. It deletes the handler +indicated by \fItoken\fR so that no call to \fIproc\fR +will be made; if that handler no longer exists +(e.g. because the time period has already elapsed and \fIproc\fR +has been invoked then \fBTcl_DeleteTimerHandler\fR does nothing. +The tokens returned by \fBTcl_CreateTimerHandler\fR never have +a value of NULL, so if NULL is passed to \fBTcl_DeleteTimerHandler\fR +then the procedure does nothing. + +.SH KEYWORDS +callback, clock, handler, timer |