view docs/man3/SDL_SemWaitTimeout.3 @ 1303:52b5afd7ecee

Date: Tue, 05 Jul 2005 21:43:26 +1000 From: Sean Childs Subject: [SDL] Compiling SDL 1.2.8 with the free Borland compiler When compiling SDL 1.2.8 with the free Borland compiler, I received this error (there is a similar error that occurs in src\video\windx5\sdl_dx5events.c): Error E2342 ..\..\src\video\windib\sdl_dibevents.c 189: Type mismatch in parameter 'lpPrevWndFunc' (wanted 'int (__stdcall *)()', got 'long (__stdcall *)(void *,unsigned int,unsigned int,long)') in function DIB_HandleMessage I checked the MSDN library at: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winui/winui/ windowsuserinterface/windowing/windowprocedures/windowprocedurereference/wind owprocedurefunctions/callwindowproc.asp and it had this to say: If STRICT is not defined, the lpPrevWndFunc parameter has the data type FARPROC. The FARPROC type is declared as follows: int (FAR WINAPI * FARPROC) () In C, the FARPROC declaration indicates a callback function that has an unspecified parameter list. In C++, however, the empty parameter list in the declaration indicates that a function has no parameters. This subtle distinction can break careless code. Following is one way to handle this situation: #ifdef STRICT WNDPROC MyWindowProcedure #else FARPROC MyWindowProcedure #endif ... lResult = CallWindowProc(MyWindowProcedure, ...)
author Sam Lantinga <slouken@libsdl.org>
date Tue, 31 Jan 2006 15:30:42 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_SemWaitTimeout" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SemWaitTimeout\- Lock a semaphore, but only wait up to a specified maximum time\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
#include "SDL_thread\&.h"
.sp
\fBint \fBSDL_SemWaitTimeout\fP\fR(\fBSDL_sem *sem, Uint32 timeout\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_SemWaitTimeout()\fP is a varient of \fISDL_SemWait\fR with a maximum timeout value\&. If the value of the semaphore pointed to by \fBsem\fR is positive (greater than zero) it will atomically decrement the semaphore value and return 0, otherwise it will wait up to \fBtimeout\fR milliseconds trying to lock the semaphore\&. This function is to be avoided if possible since on some platforms it is implemented by polling the semaphore every millisecond in a busy loop\&.
.PP
After \fBSDL_SemWaitTimeout()\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&.
.SH "RETURN VALUE"
.PP
Returns \fB0\fR if the semaphore was successfully locked or either \fBSDL_MUTEX_TIMEOUT\fR or \fB-1\fR if the timeout period was exceeded or there was an error, respectivly\&.
.PP
If the semaphore was not successfully locked, the semaphore will be unchanged\&.
.SH "EXAMPLES"
.PP
.PP
.nf
\f(CWres = SDL_SemWaitTimeout(my_sem, WAIT_TIMEOUT_MILLISEC);

if (res == SDL_MUTEX_TIMEOUT) {
        return TRY_AGAIN;
}
if (res == -1) {
        return WAIT_ERROR;
}

\&.\&.\&.

SDL_SemPost(my_sem);\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\fP\fR, \fI\fBSDL_SemTryWait\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00