xref: /freebsd/share/man/man3/pthread_mutex_timedlock.3 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)

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.Dd August 7, 2019
.Dt PTHREAD_MUTEX_TIMEDLOCK 3
.Os
.Sh NAME
.Nm pthread_mutex_timedlock
.Nd lock a mutex without blocking indefinitely
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.In time.h
.Ft int
.Fn pthread_mutex_timedlock "pthread_mutex_t *restrict mutex" "const struct timespec *restrict abs_timeout"
.Sh DESCRIPTION
The
.Fn pthread_mutex_timedlock
function will lock
.Fa mutex .
If it is already locked the calling thread will block until
the mutex becomes available or
the timeout,
specified by abs_timeout,
expires.
The time of the timeout is an absolute time and
is not relative to the current time.
.Sh RETURN VALUES
If successful,
.Fn pthread_mutex_timedlock
will return zero, otherwise an error number will be returned to
indicate the error.
.Sh ERRORS
The
.Fn pthread_mutex_timedlock
function will fail if:
.Bl -tag -width Er
.It Bq "Er ENOTRECOVERABLE"
The
.Fa mutex
was created with the protocol attribute having the
value PTHREAD_PRIO_PROTECT and
the calling thread's priority is higher than the
mutex's current priority ceiling.
.It Bq Er EINVAL
The process or thread would have blocked, and
.Fa abs_timeout
specified a nanosecond value less than zero or
greater than or equal to 1 billion.
.It Bq Er EINVAL
The
.Fa mutex
parameter is invalid.
.It Bq Er ETIMEDOUT
The
.Fa mutex
could not be locked before the timeout expired.
.It Bq Er EAGAIN
The
.Fa mutex
could not be acquired because the
maximum number of recursive locks for the
.Fa mutex
has been exceeded.
.It Bq Er EDEADLK
The current thread already owns the
.Fa mutex .
.It Bq Er EOWNERDEAD
The argument
.Fa mutex
points to a robust mutex and the process containing the previous owning
thread terminated while holding the mutex lock.
The lock was granted to the caller and it is up to the new owner
to make the state consistent.
.It Bq Er ENOTRECOVERABLE
The state protected by the
.Fa mutex
is not recoverable.
.El
.Sh SEE ALSO
.Xr pthread_mutex_consistent 3 ,
.Xr pthread_mutex_destroy 3 ,
.Xr pthread_mutex_init 3 ,
.Xr pthread_mutex_lock 3 ,
.Xr pthread_mutex_trylock 3 ,
.Xr pthread_mutex_unlock 3
.Sh STANDARDS
The
.Fn pthread_mutex_timedlock
function is expected to conform to
.St -p1003.1-96 .