Tribblix: manual page: pthread_mutex

PTHREAD_MUTEX_CONSISTENT(3C) Standard C Library Functions

NAME

pthread_mutex_consistent - mark state protected by robust mutex as
consistent

SYNOPSIS

#include <pthread.h>

int
pthread_mutex_consistent(pthread_mutex_t *mutex);

DESCRIPTION

The pthread_mutex_consistent() function is used to indicate that a
robust lock that is in an inconsistent state no longer is.

A robust lock enters into an inconsistent state when a process or
thread holding a robust lock exits, such as by calling exit(2) or
thr_exit(3C), or crashes without unlocking the lock. At that point, if
another process or thread is currently in a call, or calls
pthread_mutex_lock(3C), it will obtain the lock; however, the error
code EOWNERDEAD will be returned. In such cases, that thread will own
the lock and must check and clean up any inconsistent state that is
protected by the lock. When finished, it must call
pthread_mutex_consistent() to indicate that it is in a consistent state
again.

If a process or thread obtains a robust lock while it is in an
inconsistent state and it crashes or terminates before marking the lock
as consistent, the next process or thread that obtains the lock will
receive EOWNERDEAD.

RETURN VALUES

Upon successful completion, the pthread_mutex_consistent() returns zero
and marks mutex as consistent. Callers of pthread_mutex_lock() will
not have EOWNERDEAD returned until another process or thread exits
without unlocking. Upon failure, an error will be returned which
corresponds to one of the errors listed below.

ERRORS

The pthread_mutex_consistent() function will fail if:

EINVAL mutex is an uninitialized mutex, not a robust mutex,
or not in an inconsistent state.

INTERFACE STABILITY