Mercurial > sdl-ios-xcode

view docs/man3/SDL_CreateSemaphore.3 @ 816:428f688f2ad2

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Date: Fri, 13 Feb 2004 17:03:16 +0100 From: Max Horn Subject: Modifier key fix The internal modifier state can get out of sync with reality. To trigger this, do for example this: 1) Launch an SDL app 2) Alt-click on the desktop (this will hide the SDL app). 3) Bring the SDL app back to the front 4) SDL will still think alt is pressed (and as such will treat left clicks like middle clicks). If you press and release alt, it'll be fine again. The attached patch cures this by rechecking the modifier state whenever we process an event.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 13 Feb 2004 17:57:16 +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