trusty (7) semaphore.h.7posix.gz
NAME
semaphore.h - semaphores (REALTIME)
SYNOPSIS
#include <semaphore.h>
DESCRIPTION
The <semaphore.h> header shall define the sem_t type, used in performing semaphore operations. The
semaphore may 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 shall be defined (see
sem_open()).
The following shall be declared as functions and may also be defined as macros. Function prototypes shall
be provided.
int sem_close(sem_t *);
int sem_destroy(sem_t *);
int sem_getvalue(sem_t *restrict, int *restrict);
int sem_init(sem_t *, int, unsigned);
sem_t *sem_open(const char *, int, ...);
int sem_post(sem_t *);
int sem_timedwait(sem_t *restrict, const struct timespec *restrict);
int sem_trywait(sem_t *);
int sem_unlink(const char *);
int sem_wait(sem_t *);
Inclusion of the <semaphore.h> header may make visible symbols defined in the headers <fcntl.h> and
<sys/types.h>.
The following sections are informative.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
<fcntl.h> , <sys/types.h> , the System Interfaces volume of IEEE Std 1003.1-2001, sem_destroy(),
sem_getvalue(), sem_init(), sem_open(), sem_post(), sem_timedwait(), sem_trywait(), sem_unlink(),
sem_wait()
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition,
Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers,
Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The
original Standard can be obtained online at http://www.opengroup.org/unix/online.html .