SDL-mirror/docs/man3/SDL_SemTryWait.3
Sam Lantinga f037300cd2 Erik Heckers fixed bug #493
Searching the installed man pages for SDL functions fails, e.g.
  man -k SDL_ |grep Video
After investigating this I found that "makewhatis", the tool that generates
the "whatis" database, reads the SDL_* man pages, but doesn't produce
entries in the "whatis" database for the SDL_* man pages.
After some more debugging I found the reason is a missing space.
After editing SDL_Init.3(.gz) and replacing
   SDL_Init\- Initializes SDL
with
   SDL_Init \- Initializes SDL
everything works fine.
After running "makewhatis" I can successfully do a
   man -k SDL_
and SDL_Init is listed in the output.

--HG--
branch : SDL-1.2
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/branches/SDL-1.2%402660
2007-12-29 02:34:53 +00:00

41 lines
1.5 KiB
Groff

.TH "SDL_SemTryWait" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference"
.SH "NAME"
SDL_SemTryWait \- Attempt to lock a semaphore but don\&'t suspend the thread\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
#include "SDL_thread\&.h"
.sp
\fBint \fBSDL_SemTryWait\fP\fR(\fBSDL_sem *sem\fR);
.SH "DESCRIPTION"
.PP
\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\&.
.PP
After \fBSDL_SemTryWait\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 thread would have suspended 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_SemTryWait(my_sem);
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_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