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35 lines
1.2 KiB
Groff
35 lines
1.2 KiB
Groff
.TH "SDL_SemWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference"
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.SH "NAME"
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SDL_SemWait\- Lock a semaphore and suspend the thread if the semaphore value is zero\&.
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.SH "SYNOPSIS"
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.PP
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\fB#include "SDL\&.h"
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#include "SDL_thread\&.h"
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.sp
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\fBint \fBSDL_SemWait\fP\fR(\fBSDL_sem *sem\fR);
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.SH "DESCRIPTION"
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.PP
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\fBSDL_SemWait()\fP suspends the calling thread until either the semaphore pointed to by \fBsem\fR has a positive value, the call is interrupted by a signal or error\&. If the call is successful it will atomically decrement the semaphore value\&.
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.PP
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After \fBSDL_SemWait()\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&.
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.SH "RETURN VALUE"
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.PP
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Returns \fB0\fR if successful or \fB-1\fR if there was an error (leaving the semaphore unchanged)\&.
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.SH "EXAMPLES"
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.PP
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.PP
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.nf
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\f(CWif (SDL_SemWait(my_sem) == -1) {
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return WAIT_FAILED;
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}
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\&.\&.\&.
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SDL_SemPost(my_sem);\fR
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.fi
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.PP
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.SH "SEE ALSO"
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.PP
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\fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemTryWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR
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...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00
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