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The new, cleaner, version of the atomic operations. The dummy code is what you should start working with to port atomic ops. The linux code appears to be complete and *should* be the base of all Unix and GCC based versions. The macosx and win32 versions are currently just copies of the dummy code. I will begin working on the windows version as soon as this check in is done. I need someone to work on the Mac OS X version. I'm afraid that this check in will break QNX (Sorry!)
author Bob Pendleton <bob@pendleton.com>
date Thu, 17 Sep 2009 20:35:12 +0000
parents 546f7c1eb755
children 1238da4a7112
rev   line source
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1 .TH "SDL_CreateSemaphore" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_CreateSemaphore \- Creates a new semaphore and assigns an initial value to it\&.
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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 \fBSDL_sem *\fBSDL_CreateSemaphore\fP\fR(\fBUint32 initial_value\fR);
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10 .SH "DESCRIPTION"
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11 .PP
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12 \fBSDL_CreateSemaphore()\fP creates a new semaphore and initializes it with the value \fBinitial_value\fR\&. Each locking operation on the semaphore by \fISDL_SemWait\fR, \fISDL_SemTryWait\fR or \fISDL_SemWaitTimeout\fR will atomically decrement the semaphore value\&. The locking operation will be blocked if the semaphore value is not positive (greater than zero)\&. Each unlock operation by \fISDL_SemPost\fR will atomically increment the semaphore value\&.
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13 .SH "RETURN VALUE"
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14 .PP
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15 Returns a pointer to an initialized semaphore or \fBNULL\fR if there was an error\&.
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16 .SH "EXAMPLES"
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17 .PP
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18 .PP
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19 .nf
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20 \f(CWSDL_sem *my_sem;
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21
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22 my_sem = SDL_CreateSemaphore(INITIAL_SEM_VALUE);
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23
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24 if (my_sem == NULL) {
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25 return CREATE_SEM_FAILED;
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26 }\fR
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27 .fi
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28 .PP
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29 .SH "SEE ALSO"
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30 .PP
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31 \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\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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32 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00