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sem(4) [freebsd man page]

SEM(4)							   BSD Kernel Interfaces Manual 						    SEM(4)

sem -- POSIX semaphores SYNOPSIS
To compile this driver into the kernel, place the following line in your kernel configuration file: options P1003_1B_SEMAPHORES Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5): sem_load="YES" To load the driver as a module at run-time, run the following command as root: kldload sem DESCRIPTION
The sem facility provides system calls used by the standard C library (libc) to implement POSIX semaphores. This facility offers support for such functions as sem_init() and sem_wait(). It is available both as a kernel option for static inclusion and as a dynamic kernel module. SEE ALSO
sem_destroy(3), sem_getvalue(3), sem_init(3), sem_open(3), sem_post(3), sem_wait(3), config(8), kldload(8), kldunload(8) HISTORY
The sem facility appeared in FreeBSD 5.0. BSD
February 7, 2014 BSD

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