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Quartz fix: ut2004 makes a 2D window for the splash screen, which sets the screen surface's pixels field. Then we tear down that video mode and create a GL context, and the Quartz target isn't resetting the pixels field to NULL. When you just create a GL window, the structure is memset'd to zero the first time through, so unless you hit ut2004's codepath, you won't see the bug. :) Without this patch, quitting a windowed ut2003/ut2004 game makes the OS dump a warning about a bogus free() to stderr, but it doesn't actually crash. All we need to do is explicitly initialize the current->pixels field.
author Ryan C. Gordon <icculus@icculus.org>
date Tue, 24 Feb 2004 06:53:22 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_CreateSemaphore" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_CreateSemaphore\- Creates a new semaphore and assigns an initial value to it\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
#include "SDL_thread\&.h"
.sp
\fBSDL_sem *\fBSDL_CreateSemaphore\fP\fR(\fBUint32 initial_value\fR);
.SH "DESCRIPTION"
.PP
\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\&.
.SH "RETURN VALUE"
.PP
Returns a pointer to an initialized semaphore or \fBNULL\fR if there was an error\&.
.SH "EXAMPLES"
.PP
.PP
.nf
\f(CWSDL_sem *my_sem;

my_sem = SDL_CreateSemaphore(INITIAL_SEM_VALUE);

if (my_sem == NULL) {
        return CREATE_SEM_FAILED;
}\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\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
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00