pthreads/pthread_mutex_trylock.3

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  30 .Dd July 30, 1998
  31 .Dt PTHREAD_MUTEX_TRYLOCK 3
  32 .Os
  33 .Sh NAME
  34 .Nm pthread_mutex_trylock
  35 .Nd attempt to lock a mutex without blocking
  36 .Sh SYNOPSIS
  37 .Fd #include <pthread.h>
  38 .Ft int
  39 .Fn pthread_mutex_trylock "pthread_mutex_t *mutex"
  40 .Sh DESCRIPTION
  41 The
  42 .Fn pthread_mutex_trylock
  43 function locks
  44 .Fa mutex .
  45 If the mutex is already locked,
  46 .Fn pthread_mutex_trylock
  47 will not block waiting for the mutex, but will return an error condition.
  48 .Sh RETURN VALUES
  49 If successful,
  50 .Fn pthread_mutex_trylock
  51 will return zero, otherwise an error number will be returned to
  52 indicate the error.
  53 .Sh ERRORS
  54 .Fn pthread_mutex_trylock
  55 will fail if:
  56 .Bl -tag -width Er
  57 .It Bq Er EINVAL
  58 The value specified by
  59 .Fa mutex
  60 is invalid.
  61 .It Bq Er EBUSY
  62 .Fa Mutex
  63 is already locked.
  64 .El
  65 .Sh SEE ALSO
  66 .Xr pthread_mutex_destroy 3 ,
  67 .Xr pthread_mutex_init 3 ,
  68 .Xr pthread_mutex_lock 3 ,
  69 .Xr pthread_mutex_unlock 3
  70 .Sh STANDARDS
  71 .Fn pthread_mutex_trylock
  72 conforms to
  73 .St -p1003.1-96 .