RecMutex

Added in version 2.32.

class RecMutex(*args, **kwargs)

The GRecMutex struct is an opaque data structure to represent a recursive mutex. It is similar to a 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 RecMutex is allocated in static storage then it can be used without initialisation. Otherwise, you should call init() on it and clear() when done.

A GRecMutex should only be accessed with the g_rec_mutex_ functions.

Methods

class RecMutex

clear() → None

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

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

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

Added in version 2.32.

init() → None

Initializes a 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 init() on an already initialized RecMutex leads to undefined behaviour.

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

Added in version 2.32.

lock() → None

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.

Added in version 2.32.

trylock() → bool

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.

Added in version 2.32.

unlock() → None

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

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

Added in version 2.32.

Fields

class RecMutex

i

p