Update manual for sem_init and sem_open, restrictions of shared semaphore

and 14 characters in name length no longer exist.

Reviewed by:	deischen@
This commit is contained in:
David Xu 2010-01-09 05:40:46 +00:00
parent 2bd661baa1
commit a455039e3a
2 changed files with 17 additions and 9 deletions

View File

@ -46,9 +46,19 @@ function initializes the unnamed semaphore pointed to by
.Fa sem
to have the value
.Fa value .
.Pp
A non-zero value for
.Fa pshared
specifies a shared semaphore that can be used by multiple processes.
specifies a shared semaphore that can be used by multiple processes,
the semaphore should be located in shared memory region (see
.Xr mmap 2 ,
.Xr shm_open 2 ,
and
.Xr shmget 2 ) ,
any process having read and write access to address
.Fa sem
can perform semaphore operations on
.Fa sem .
.Pp
Following a successful call to
.Fn sem_init ,

View File

@ -58,6 +58,12 @@ The returned semaphore may be used in subsequent calls to
and
.Fn sem_close .
.Pp
This implementation places strict requirements on the value of
.Fa name :
it must begin with a slash
.Pq Ql / ,
contain no other slash characters.
.Pp
The following bits may be set in the
.Fa oflag
argument:
@ -217,11 +223,3 @@ functions conform to
.Sh HISTORY
Support for named semaphores first appeared in
.Fx 5.0 .
.Sh BUGS
This implementation places strict requirements on the value of
.Fa name :
it must begin with a slash
.Pq Ql / ,
contain no other slash characters,
and be less than 14 characters in length
not including the terminating null character.