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33 .Nd register thread locking methods with the dynamic linker
39 .Fn dllockinit "void *context" "void *(*lock_create)(void *context)" "void (*rlock_acquire)(void *lock)" "void (*wlock_acquire)(void *lock)" "void (*lock_release)(void *lock)" "void (*lock_destroy)(void *lock)" "void (*context_destroy)(void *context)"
42 Due to enhancements in the dynamic linker, this interface is no longer
44 It is deprecated and will be removed from future releases.
45 In current releases it still exists, but only as a stub which does nothing.
48 Threads packages can call
50 at initialization time to register locking functions for the dynamic
52 This enables the dynamic linker to prevent multiple
53 threads from entering its critical sections simultaneously.
57 argument specifies an opaque context for creating locks.
59 dynamic linker will pass it to the
61 function when creating the locks it needs.
62 When the dynamic linker
63 is permanently finished using the locking functions (e.g., if the
64 program makes a subsequent call to
66 to register new locking functions) it will call
68 to destroy the context.
72 argument specifies a function for creating a read/write lock.
74 must return a pointer to the new lock.
80 arguments specify functions which lock a lock for reading or
81 writing, respectively.
84 argument specifies a function which unlocks a lock.
86 functions is passed a pointer to the lock.
90 argument specifies a function to destroy a lock.
93 if locks do not need to be destroyed.
96 argument specifies a function to destroy the context.
99 if the context does not need to be destroyed.
103 is called, the dynamic linker protects its critical sections using
104 a default locking mechanism which works by blocking the
110 This is sufficient for many application level threads
111 packages, which typically use one of these signals to implement
113 An application which has registered its own locking
116 can restore the default locking by calling
126 function first appeared in