sem: Named POSIX Semaphores
In gfkse/bettermc: Enhanced Fork-Based Parallelization

sem	R Documentation

Named POSIX Semaphores

Description

Named POSIX Semaphores

Usage

sem_open(name, create = FALSE, overwrite = FALSE, value = 0)

sem_post(sem)

sem_wait(sem)

sem_close(sem)

sem_unlink(name)

Arguments

`name`	the name of the semaphore. Consult `man sem_overview` for what makes a valid name.
`create`	should the semaphore be created if it currently does not exist?
`overwrite`	if `create == TRUE`, should we overwrite an already existing semaphore with the name (`TRUE`) or rather fail (`FALSE`).
`value`	the initial value of the semaphore (`>= 0`).
`sem`	an object as returned by `sem_open`.

Value

For sem_open, an object of class "sem", which is an external pointer to the POSIX semaphore. All other functions return NULL invisibly and are called for their side effects.