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1 | .TH "SDL_CreateSemaphore" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" |
2 | .SH "NAME" |
3 | SDL_CreateSemaphore \- Creates a new semaphore and assigns an initial value to it\&. |
4 | .SH "SYNOPSIS" |
5 | .PP |
6 | \fB#include "SDL\&.h" |
7 | #include "SDL_thread\&.h" |
8 | .sp |
9 | \fBSDL_sem *\fBSDL_CreateSemaphore\fP\fR(\fBUint32 initial_value\fR); |
10 | .SH "DESCRIPTION" |
11 | .PP |
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\&. |
13 | .SH "RETURN VALUE" |
14 | .PP |
15 | Returns a pointer to an initialized semaphore or \fBNULL\fR if there was an error\&. |
16 | .SH "EXAMPLES" |
17 | .PP |
18 | .PP |
19 | .nf |
20 | \f(CWSDL_sem *my_sem; |
21 | |
22 | my_sem = SDL_CreateSemaphore(INITIAL_SEM_VALUE); |
23 | |
24 | if (my_sem == NULL) { |
25 | return CREATE_SEM_FAILED; |
26 | }\fR |
27 | .fi |
28 | .PP |
29 | .SH "SEE ALSO" |
30 | .PP |
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 |
32 | .\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00 |