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From: Tyler Montbriand <tsm@accesscomm.ca> To: sdl@libsdl.org Date: Fri, 30 Sep 2005 02:24:50 -0600 Subject: [SDL] WinCE timers, continued Here's a strange timer for Windows CE that doesn't ignore time across suspends. It uses GetSystemTime to keep the time continuous, and GetTicks to get finer-grained readings than 1 second. It detects the difference between the GetTicks time and GetSystemTime time on power-on to keep the error within one second max. It's not a patch on the current win32 timer code -- took one look at that and figured it had more than enough #ifdefs already. It's windows-ce specific. Another thing I've noticed is that the Windows CE 4.0 and newer API has functions warn processes about suspends. This is something SDL REALLY needs for audio in particular, because turning it off while it's playing causes anything that uses audio to hardlock the system on power-on. Unfortunately I don't have 4.0 to play with. :(
author Ryan C. Gordon <icculus@icculus.org>
date Tue, 22 Nov 2005 07:10:07 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
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e5bc29de3f0a Updated from the SDL Documentation Project
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1 .TH "SDL_SemWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_SemWait\- Lock a semaphore and suspend the thread if the semaphore value is zero\&.
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4 .SH "SYNOPSIS"
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5 .PP
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6 \fB#include "SDL\&.h"
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7 #include "SDL_thread\&.h"
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8 .sp
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9 \fBint \fBSDL_SemWait\fP\fR(\fBSDL_sem *sem\fR);
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10 .SH "DESCRIPTION"
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11 .PP
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12 \fBSDL_SemWait()\fP suspends the calling thread until either the semaphore pointed to by \fBsem\fR has a positive value, the call is interrupted by a signal or error\&. If the call is successful it will atomically decrement the semaphore value\&.
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13 .PP
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14 After \fBSDL_SemWait()\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&.
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15 .SH "RETURN VALUE"
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16 .PP
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17 Returns \fB0\fR if successful or \fB-1\fR if there was an error (leaving the semaphore unchanged)\&.
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18 .SH "EXAMPLES"
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19 .PP
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20 .PP
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21 .nf
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22 \f(CWif (SDL_SemWait(my_sem) == -1) {
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23 return WAIT_FAILED;
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24 }
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25
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26 \&.\&.\&.
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27
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28 SDL_SemPost(my_sem);\fR
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29 .fi
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30 .PP
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31 .SH "SEE ALSO"
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32 .PP
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33 \fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemTryWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR
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34 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00