pthreads/pthread_getspecific.3

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  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 SYNOPSIS
  40 .Fd #include <pthread.h>
  41 .Ft void *
  42 .Fn pthread_getspecific "pthread_key_t key"
  43 .Sh DESCRIPTION
  44 The
  45 .Fn pthread_getspecific
  46 function returns the value currently bound to the specified
  47 .Fa key
  48 on behalf of the calling thread.
  49 .Pp
  50 The effect of calling
  51 .Fn pthread_getspecific
  52 with a
  53 .Fa key
  54 value not obtained from
  55 .Fn pthread_key_create
  56 or after
  57 .Fa key
  58 has been deleted with
  59 .Fn pthread_key_delete
  60 is undefined.
  61 .Pp
  62 .Fn pthread_getspecific
  63 may be called from a thread-specific data destructor function.
  64 .Sh RETURN VALUES
  65 The
  66 .Fn pthread_getspecific
  67 function will return the thread-specific data value associated with the given
  68 .Fa key .
  69 If no thread-specific data value is associated with
  70 .Fa key ,
  71 then the value NULL is returned.
  72 .Sh ERRORS
  73 None.
  74 .Sh SEE ALSO
  75 .Xr pthread_key_create 3 ,
  76 .Xr pthread_key_delete 3 ,
  77 .Xr pthread_setspecific 3
  78 .Sh STANDARDS
  79 .Fn pthread_getspecific
  80 conforms to
  81 .St -p1003.1-96 .