Function linuxcnc_hal_sys::rtapi_sem_take

pub unsafe extern "C" fn rtapi_sem_take(sem_id: c_int) -> c_int

‘rtapi_sem_take()’ locks a semaphore. Returns 0 or -EINVAL. If the semaphore is unlocked it returns 0 immediately. If the semaphore is locked, the calling task blocks until the semaphore is unlocked, then it returns 0. Call only from within a realtime task.