view docs/man3/SDL_SemWaitTimeout.3 @ 2079:1ed2155b7ee4

From: Torsten Giebl Subject: ALLOCA Patch for SDL-1.2 Newsgroups: gmane.comp.lib.sdl Date: 2006-10-24 00:31:16 GMT Hello ! As alloca.h is not available on CYGWIN and MinGW32 it should not be checked there or it should be checked with -mno-cygwin using. I am a total configure.in newbie, but i found the way that things are handled in configure.in pretty bad for the case CYGWIN with MinGW Mode or not. Maybe this is not possible but i would like to have a way to detect at the start for example CYGWIN and then add. ask if configure was called with --enable-cygwin for example. --enable-cygwin should be optional and disabled by default as we want to have MinGW Mode by default. Only if the user wants it he should be able to use it. Then the whole configure.in would get add. questions okay the system is CYGWIN with or without MinGW Mode. The alloca.h thing for example is only available under CYGWIN ( without MinGW Mode ). CU
author Ryan C. Gordon <icculus@icculus.org>
date Fri, 01 Dec 2006 20:25:03 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_SemWaitTimeout" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SemWaitTimeout\- Lock a semaphore, but only wait up to a specified maximum time\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
#include "SDL_thread\&.h"
.sp
\fBint \fBSDL_SemWaitTimeout\fP\fR(\fBSDL_sem *sem, Uint32 timeout\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_SemWaitTimeout()\fP is a varient of \fISDL_SemWait\fR with a maximum timeout value\&. If the value of the semaphore pointed to by \fBsem\fR is positive (greater than zero) it will atomically decrement the semaphore value and return 0, otherwise it will wait up to \fBtimeout\fR milliseconds trying to lock the semaphore\&. This function is to be avoided if possible since on some platforms it is implemented by polling the semaphore every millisecond in a busy loop\&.
.PP
After \fBSDL_SemWaitTimeout()\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&.
.SH "RETURN VALUE"
.PP
Returns \fB0\fR if the semaphore was successfully locked or either \fBSDL_MUTEX_TIMEOUT\fR or \fB-1\fR if the timeout period was exceeded or there was an error, respectivly\&.
.PP
If the semaphore was not successfully locked, the semaphore will be unchanged\&.
.SH "EXAMPLES"
.PP
.PP
.nf
\f(CWres = SDL_SemWaitTimeout(my_sem, WAIT_TIMEOUT_MILLISEC);

if (res == SDL_MUTEX_TIMEOUT) {
        return TRY_AGAIN;
}
if (res == -1) {
        return WAIT_ERROR;
}

\&.\&.\&.

SDL_SemPost(my_sem);\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\fP\fR, \fI\fBSDL_SemTryWait\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00