07-29-2003
making use of a Semaphore
can any one tell me how to run a semaphore. i understand roughly how they work code wise, but i'm not sure how to make use of them. i have two client programs in csh that perform tasks on a server file (flat file) how the i get the semaphore to lock the file when one has accessed it and how to use it to prevent deadlock. Is it done by accessing the file through the semaphore?
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LEARN ABOUT OPENSOLARIS
semaphore.h
semaphore.h(3HEAD) Headers semaphore.h(3HEAD)
NAME
semaphore.h, semaphore - semaphores
SYNOPSIS
#include <semaphore.h>
DESCRIPTION
The <semaphore.h> header defines the sem_t type, used in performing semaphore operations. The semaphore can be implemented using a file
descriptor, in which case applications are able to open up at least a total of {OPEN_MAX} files and semaphores. The symbol SEM_FAILED is
defined (see sem_open(3C)).
Inclusion of the <semaphore.h> header can make visible symbols defined in the headers <fcntl.h> and <sys/types.h>. See fcntl.h(3HEAD) and
types.h(3HEAD).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Committed |
+-----------------------------+-----------------------------+
|Standard |See standards(5). |
+-----------------------------+-----------------------------+
SEE ALSO
fcntl.h(3HEAD), types.h(3HEAD), sem_destroy(3C), sem_getvalue(3C), sem_init(3C), sem_open(3C), sem_post(3C), sem_timedwait(3C),
sem_unlink(3C), sem_wait(3C), attributes(5), standards(5)
SunOS 5.11 5 Feb 2008 semaphore.h(3HEAD)