xref: /freebsd/share/man/man3/pthread_getspecific.3 (revision 0f7d684755aefbcfd70b45d24efc2d39bc505c4c)
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31.Dd April 4, 1996
32.Dt PTHREAD_GETSPECIFIC 3
33.Os BSD 4
34.Sh NAME
35.Nm pthread_getspecific
36.Nd get a thread-specific data value
37.Sh SYNOPSIS
38.Fd #include <pthread.h>
39.Ft void *
40.Fn pthread_getspecific "pthread_key_t key"
41.Sh DESCRIPTION
42The
43.Fn pthread_getspecific
44function returns the value currently bound to the specified
45.Fa key
46on behalf of the calling thread.
47.Pp
48The effect of calling
49.Fn pthread_getspecific
50with a
51.Fa key
52value not obtained from
53.Fn pthread_key_create
54or after
55.Fa key
56has been deleted with
57.Fn pthread_key_delete
58is undefined.
59.Pp
60.Fn pthread_getspecific
61may be called from a thread-specific data destructor function.
62.Sh RETURN VALUES
63The
64.Fn pthread_getspecific
65function will return the thread-specific data value associated with the given
66.Fa key .
67If no thread-specific data value is associated with
68.Fa key ,
69then the value NULL is returned.
70.Sh ERRORS
71None.
72.Sh SEE ALSO
73.Xr pthread_key_create 3 ,
74.Xr pthread_key_delete 3
75.Xr pthread_setspecific 3
76.Sh STANDARDS
77.Fn pthread_getspecific
78is expected to conform to IEEE
79.Pq Dq Tn POSIX
80Std 1003.1c when it is published.
81