Class (GI Struct)

GLib-2.0 ▶ GLib ▶ RecMutexSince 2.32

The GRecMutex struct is an opaque data structure to represent a recursive mutex. It is similar to a GLib.Mutex with the difference that it is possible to lock a GRecMutex multiple times in the same thread without deadlock. When doing so, care has to be taken to unlock the recursive mutex as often as it has been locked.

If a GLib.RecMutex is allocated in static storage then it can be used without initialisation. Otherwise, you should call g_rec_mutex_init() on it and g_rec_mutex_clear() when done.

A GRecMutex should only be accessed with the g_rec_mutex_ functions.

2.32

Index
constructor
$gtype
clear init lock trylock unlock
$gtype: GType<RecMutex>

  • Frees the resources allocated to a recursive mutex with g_rec_mutex_init().

    This function should not be used with a GLib.RecMutex that has been statically allocated.

    Calling g_rec_mutex_clear() on a locked recursive mutex leads to undefined behaviour.

    Returns void

    2.32

  • Initializes a GLib.RecMutex so that it can be used.

    This function is useful to initialize a recursive mutex that has been allocated on the stack, or as part of a larger structure.

    It is not necessary to initialise a recursive mutex that has been statically allocated.

      typedef struct {
        GRecMutex m;
        ...
      } Blob;

    Blob *b;

    b = g_new (Blob, 1);
    g_rec_mutex_init (&b->m);

    Calling g_rec_mutex_init() on an already initialized GLib.RecMutex leads to undefined behaviour.

    To undo the effect of g_rec_mutex_init() when a recursive mutex is no longer needed, use g_rec_mutex_clear().

    Returns void

    2.32

  • Locks rec_mutex. If rec_mutex is already locked by another thread, the current thread will block until rec_mutex is unlocked by the other thread. If rec_mutex is already locked by the current thread, the 'lock count' of rec_mutex is increased. The mutex will only become available again when it is unlocked as many times as it has been locked.

    Returns void

    2.32

  • Tries to lock rec_mutex. If rec_mutex is already locked by another thread, it immediately returns false. Otherwise it locks rec_mutex and returns true.

    Returns boolean

    true if rec_mutex could be locked

    2.32

  • Unlocks rec_mutex. If another thread is blocked in a g_rec_mutex_lock() call for rec_mutex, it will become unblocked and can lock rec_mutex itself.

    Calling g_rec_mutex_unlock() on a recursive mutex that is not locked by the current thread leads to undefined behaviour.

    Returns void

    2.32