view docs/man3/SDL_CreateSemaphore.3 @ 2268:4baee598306d

Date: Thu, 05 Jul 2007 14:02:33 -0700 From: Sam Lantinga Subject: SDL 1.3 keyboard plan After lots of discussion with Christian, this is what we came up with: > So, to sum up... > SDLK_* become the physical keys, starting at > (1<<21) > We create a macro SDLK_INDEX(X) > We have two functions SDL_GetLayoutKey(SDLKey) and SDL_GetKeyName() > SDL_GetLayoutKey maps to UCS4 for printable characters, and SDLK* for non-printable characters > and does so based on the OS's current keyboard layout > SDL_GetKeyName() handles both SDLK_* and UCS4, converting UCS4 to UTF-8 and converting SDLK_* into our names, which are UTF-8 for printable characters. > WASD folks use SDLK_*, and 'I' folks use SDL_GetLayoutKey(SDLK_*) Here is the patch he came up with, and his e-mail about it: Date: Fri, 17 Aug 2007 19:50:28 +0200 From: Christian Walther Subject: Re: SDL 1.3 keyboard plan > Sounds great, go ahead and send me a patch. Here goes! Thanks for having a look. Don't hesitate to comment if anything does not conform to your ideas. One caveat: Committing this now may break compilability of some video drivers - specifically, if they use any of the SDLK_* codes that were obsoleted and moved into SDL_compat.h. I only tried Cocoa (which did break, but is already fixed) and X11 (which didn't, but then its key handling is #iffed out). If that's a problem, it may need to go into a branch. -Christian
author Sam Lantinga <slouken@libsdl.org>
date Sun, 19 Aug 2007 14:52:52 +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