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Fixed bug #80 Date: 21 Apr 2003 17:20:20 +0100 From: Alan Swanson <swanson@uklinux.net> Subject: [SDL] New XFree 4.3 Video Mode Patch If you look at the unsorted list of modes returned by X, here's mine; 1280 x 1024 @ 85.0 > 1024 x 768 @ 100.3 > USER 800 x 600 @ 125.5 > SET 640 x 480 @ 124.9 > 1280 x 1024 @ 75.0 ] 1280 x 1024 @ 60.0 ] 1280 x 960 @ 85.0 ] X11 1280 x 960 @ 60.0 ] AUTO 1152 x 864 @ 75.0 ]=20 1152 x 768 @ 54.8 ] 960 x 720 @ 120.0 ] ... 640 x 400 @ 85.1 ] 256k 576 x 432 @ 150.0 ] 249k PIXEL 640 x 350 @ 85.1 ] 224k COUNT 576 x 384 @ 109.6 ] 221k ... The user set modes come first followed by X set modes which are ordered by decreasing number of pixels and refresh. The reason why every other library or program not using SDL working is due to SDL scanning the modes in reverse getting X11 provided modes modes with the lowest refresh.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 05 May 2006 05:50:26 +0000
parents 355632dca928
children
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>SDL_CreateSemaphore</H1
><DIV
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><A
NAME="AEN7936"
></A
><H2
>Name</H2
>SDL_CreateSemaphore&nbsp;--&nbsp;Creates a new semaphore and assigns an initial value to it.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
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><H2
>Synopsis</H2
><DIV
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"
#include "SDL_thread.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_sem *<B
CLASS="FSFUNC"
>SDL_CreateSemaphore</B
></CODE
>(Uint32 initial_value);</CODE
></P
><P
></P
></DIV
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><DIV
CLASS="REFSECT1"
><A
NAME="AEN7946"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_CreateSemaphore()</TT
> creates a new semaphore and
initializes it with the value <TT
CLASS="PARAMETER"
><I
>initial_value</I
></TT
>.
Each locking operation on the semaphore by
<A
HREF="sdlsemwait.html"
>SDL_SemWait</A
>,
<A
HREF="sdlsemtrywait.html"
>SDL_SemTryWait</A
> or
<A
HREF="sdlsemwaittimeout.html"
>SDL_SemWaitTimeout</A
>
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
<A
HREF="sdlsempost.html"
>SDL_SemPost</A
>
will atomically increment the semaphore value.</P
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><H2
>Return Value</H2
><P
>Returns a pointer to an initialized semaphore or
<SPAN
CLASS="RETURNVALUE"
>NULL</SPAN
> if there was an error.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7959"
></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>SDL_sem *my_sem;

my_sem = SDL_CreateSemaphore(INITIAL_SEM_VALUE);

if (my_sem == NULL) {
        return CREATE_SEM_FAILED;
}</PRE
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>See Also</H2
><P
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><TT
CLASS="FUNCTION"
>SDL_DestroySemaphore</TT
></A
>,
<A
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><TT
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>SDL_SemWait</TT
></A
>,
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><TT
CLASS="FUNCTION"
>SDL_SemTryWait</TT
></A
>,
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><TT
CLASS="FUNCTION"
>SDL_SemWaitTimeout</TT
></A
>,
<A
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><TT
CLASS="FUNCTION"
>SDL_SemPost</TT
></A
>,
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><TT
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>SDL_SemValue</TT
></A
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