xref: /freebsd/share/man/man3/pthread_getspecific.3 (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1.\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>.
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31.\" $FreeBSD$
32.\"
33.Dd April 4, 1996
34.Dt PTHREAD_GETSPECIFIC 3
35.Os
36.Sh NAME
37.Nm pthread_getspecific
38.Nd get a thread-specific data value
39.Sh LIBRARY
40.Lb libc_r
41.Lb libpthread
42.Lb libthr
43.Sh SYNOPSIS
44.In pthread.h
45.Ft void *
46.Fn pthread_getspecific "pthread_key_t key"
47.Sh DESCRIPTION
48The
49.Fn pthread_getspecific
50function returns the value currently bound to the specified
51.Fa key
52on behalf of the calling thread.
53.Pp
54The effect of calling
55.Fn pthread_getspecific
56with a
57.Fa key
58value not obtained from
59.Fn pthread_key_create
60or after
61.Fa key
62has been deleted with
63.Fn pthread_key_delete
64is undefined.
65.Pp
66The
67.Fn pthread_getspecific
68function may be called from a thread-specific data destructor function.
69.Sh RETURN VALUES
70The
71.Fn pthread_getspecific
72function will return the thread-specific data value associated with the given
73.Fa key .
74If no thread-specific data value is associated with
75.Fa key ,
76then the value NULL is returned.
77.Sh ERRORS
78None.
79.Sh SEE ALSO
80.Xr pthread_key_create 3 ,
81.Xr pthread_key_delete 3 ,
82.Xr pthread_setspecific 3
83.Sh STANDARDS
84The
85.Fn pthread_getspecific
86function conforms to
87.St -p1003.1-96 .
88