Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_SemTryWait.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 |
| rev | line source |
|---|---|
|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
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1 .TH "SDL_SemTryWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" |
| 0 | 2 .SH "NAME" |
| 3 SDL_SemTryWait\- Attempt to lock a semaphore but don\&'t suspend the thread\&. | |
| 4 .SH "SYNOPSIS" | |
| 5 .PP | |
| 6 \fB#include "SDL\&.h" | |
| 7 #include "SDL_thread\&.h" | |
| 8 .sp | |
| 9 \fBint \fBSDL_SemTryWait\fP\fR(\fBSDL_sem *sem\fR); | |
| 10 .SH "DESCRIPTION" | |
| 11 .PP | |
| 12 \fBSDL_SemTryWait\fP is a non-blocking varient of \fI\fBSDL_SemWait\fP\fR\&. If the value of the semaphore pointed to by \fBsem\fR is positive it will atomically decrement the semaphore value and return 0, otherwise it will return \fBSDL_MUTEX_TIMEOUT\fR instead of suspending the thread\&. | |
| 13 .PP | |
| 14 After \fBSDL_SemTryWait\fP is successful, the semaphore can be released and its count atomically incremented by a successful call to \fISDL_SemPost\fR\&. | |
| 15 .SH "RETURN VALUE" | |
| 16 .PP | |
| 17 Returns \fB0\fR if the semaphore was successfully locked or either \fBSDL_MUTEX_TIMEOUT\fR or \fB-1\fR if the thread would have suspended or there was an error, respectivly\&. | |
| 18 .PP | |
| 19 If the semaphore was not successfully locked, the semaphore will be unchanged\&. | |
| 20 .SH "EXAMPLES" | |
| 21 .PP | |
| 22 .PP | |
| 23 .nf | |
| 24 \f(CWres = SDL_SemTryWait(my_sem); | |
| 25 | |
| 26 if (res == SDL_MUTEX_TIMEOUT) { | |
| 27 return TRY_AGAIN; | |
| 28 } | |
| 29 if (res == -1) { | |
| 30 return WAIT_ERROR; | |
| 31 } | |
| 32 | |
| 33 \&.\&.\&. | |
| 34 | |
| 35 SDL_SemPost(my_sem);\fR | |
| 36 .fi | |
| 37 .PP | |
| 38 .SH "SEE ALSO" | |
| 39 .PP | |
| 40 \fI\fBSDL_CreateSemaphore\fP\fR, \fI\fBSDL_DestroySemaphore\fP\fR, \fI\fBSDL_SemWait\fP\fR, \fI\fBSDL_SemWaitTimeout\fP\fR, \fI\fBSDL_SemPost\fP\fR, \fI\fBSDL_SemValue\fP\fR | |
|
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
41 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00 |