q_wait3
Return the next job from the queue, when available
Usage
#include <librecast/q.h>
int q_wait(q_t *q, q_job_t *job); int q_trywait(q_t *q, q_job_t *job);
Compile and link with -llibrecast.
Library
Librecast library (liblibrecast, -llibrecast)
Overview
q_wait() atomically fetches the next job in q and sets the job pointer to it. The call blocks until a job is available.
q_trywait() is the same as q_wait() except that if the queue read lock cannot be immediately obtained, then the call returns an error (errno set to EAGAIN) instead of blocking.
Return value
The q_push() function returns zero on success. On error, -1 is returned and errno is set to indicate the error.
Errors
The function can also fail with the errors for sem_post(3) or sem_wait(3).