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.Dd January 31, 2003
.Dt PTHREAD_ATTR_GET_NP 3
.Os
.Sh NAME
.Nm pthread_attr_get_np
.Nd get attributes of existent thread
.Sh LIBRARY
.Lb libc_r
.Sh SYNOPSIS
.In pthread_np.h
.Ft int
.Fn pthread_attr_get_np "pthread_t pid" "pthread_attr_t *dst"
.Sh DESCRIPTION
The
.Fn pthread_attr_get_np
function is used to get existent thread's attributes.
Most fields of
.Vt pthread_attr_t
structure are exact values of attributes provided at thread creation
time (as parameter to
.Fn pthread_create
function), except stack address.
.Pp
Value returned as
.Fa dst
is supposed to be used in conjunction with
.Fn pthread_attr_get*
functions to retrieve individual values from
.Vt pthread_attr_t
structure.
Parameter
.Fa dst
should point to allocated memory area big enough to fit this structure.
.Pp
It is HIGHLY RECOMMENDED to use
.Xr pthread_attr_init 3
function to allocate attribute storage.
.Sh IMPLEMENTATION DETAILS
The
.Fn pthread_attr_get_np
function will always return pointer to thread's real stack address
regardless to its value in original attributes structure.
.Sh EXAMPLES
.Bd -literal
size_t
my_thread_stack_size(pthread_t pid)
{
    pthread_attr_t attr;
    size_t size;

    pthread_attr_init(&attr);
    pthread_attr_get_np(pid, &attr);
    pthread_attr_getstacksize(&attr, &size);
    pthread_attr_destroy(&attr);
    return(size);
}
.Ed
.Sh RETURN VALUES
If successful,
.Fn pthread_attr_get_np
function returns 0.
Otherwise, an error number is returned to indicate the error.
.Sh ERRORS
.Fn pthread_attr_get_np
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
Invalid value for one of given parameters.
.It Bq Er ESRC
No thread could be found corresponding to that specified by the given
thread ID.
.El
.Sh SEE ALSO
.Xr pthread_attr_destroy 3 ,
.Xr pthread_attr_getdetachstate 3 ,
.Xr pthread_attr_getinheritsched 3 ,
.Xr pthread_attr_getschedparam 3 ,
.Xr pthread_attr_getschedpolicy 3 ,
.Xr pthread_attr_getscope 3 ,
.Xr pthread_attr_getstack 3 ,
.Xr pthread_attr_getstackaddr 3 ,
.Xr pthread_attr_getstacksize 3 ,
.Xr pthread_attr_init 3