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1 .TH "SDL_SemWait" "3" "Mon 12 Mar 2001, 01:04" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_SemWait\- Lock a semaphore and suspend the thread if the semaphore value is zero\&.
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4 .SH "SYNOPSIS"
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5 .PP
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6 \fB#include "SDL\&.h"
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7 #include "SDL_thread\&.h"
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8 .sp
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9 \fBint \fBSDL_SemWait\fP\fR(\fBSDL_sem *sem\fR);
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10 .SH "DESCRIPTION"
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11 .PP
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12 \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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13 .PP
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14 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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15 .SH "RETURN VALUE"
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16 .PP
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17 Returns \fB0\fR if successful or \fB-1\fR if there was an error (leaving the semaphore unchanged)\&.
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18 .SH "EXAMPLES"
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19 .PP
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20 .PP
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21 .nf
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22 \f(CWif (SDL_SemWait(my_sem) == -1) {
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23 return WAIT_FAILED;
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24 }
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25
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26 \&.\&.\&.
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27
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28 SDL_SemPost(my_sem);\fR
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29 .fi
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30 .PP
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31 .SH "SEE ALSO"
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32 .PP
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33 \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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34 ...\" created by instant / docbook-to-man, Mon 12 Mar 2001, 01:04
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