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Full Discussion: making use of a Semaphore
Top Forums Shell Programming and Scripting making use of a Semaphore Post 38889 by FDavid on Tuesday 29th of July 2003 09:14:22 PM
Old 07-29-2003
Lightbulb 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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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)
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