Mercurial > sdl-ios-xcode
view docs/man3/SDL_CreateSemaphore.3 @ 911:04a403e4ccf5
Date: Mon, 3 May 2004 03:15:01 +0100
From: David Symmonds
Subject: SDL Typedef Structs
Hi, Thanks for the SDL libraries, I have been using them for about a year
now and they are really brilliant. One thing that I have just found whilst
using them through C++ (and needing forward declarations) is that when you
typedef structs you sometimes use
typedef struct Name
{
...
}Name;
e.g. SDL_Surface
and other times use
typedef struct
{
...
}Name;
e.g. SDL_Rect
The first type works fine, when I define a header file I can just put
'struct Name;' at the top and use the Name throughout. However, the second
type is harder to use in a header, and I haven't found a way yet, other than
to include 'SDL.h' in the header file (undesirable). Would there be any harm
in changing the definition of SDL_Rect and such like to the second form?
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sun, 18 Jul 2004 22:57:40 +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