.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "PTHREAD_ATTR_GETSTACKADDR" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" pthread_attr_getstackaddr 
.SH NAME
pthread_attr_getstackaddr, pthread_attr_setstackaddr \- get and set
the stackaddr attribute
.SH SYNOPSIS
.LP
\fB#include <pthread.h>
.br
.sp
\fP
.LP
\fBint pthread_attr_getstackaddr(const pthread_attr_t *restrict\fP
\fIattr\fP\fB,
.br
\ \ \ \ \ \  void **restrict\fP \fIstackaddr\fP\fB);
.br
int pthread_attr_setstackaddr(pthread_attr_t *\fP\fIattr\fP\fB, void
*\fP\fIstackaddr\fP\fB); \fP
\fB
.br
\fP
.SH DESCRIPTION
.LP
The \fIpthread_attr_getstackaddr\fP() and \fIpthread_attr_setstackaddr\fP()
functions, respectively, shall get and set the
thread creation \fIstackaddr\fP attribute in the \fIattr\fP object.
.LP
The \fIstackaddr\fP attribute specifies the location of storage to
be used for the created thread's stack. The size of the
storage shall be at least {PTHREAD_STACK_MIN}.
.SH RETURN VALUE
.LP
Upon successful completion, \fIpthread_attr_getstackaddr\fP() and
\fIpthread_attr_setstackaddr\fP() shall return a value of 0;
otherwise, an error number shall be returned to indicate the error.
.LP
The \fIpthread_attr_getstackaddr\fP() function stores the \fIstackaddr\fP
attribute value in \fIstackaddr\fP if
successful.
.SH ERRORS
.LP
No errors are defined.
.LP
These functions shall not return an error code of [EINTR].
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
None.
.SH APPLICATION USAGE
.LP
The specification of the \fIstackaddr\fP attribute presents several
ambiguities that make portable use of these interfaces
impossible. The description of the single address parameter as a "stack"
does not specify a particular relationship between the
address and the "stack" implied by that address. For example, the
address may be taken as the low memory address of a buffer
intended for use as a stack, or it may be taken as the address to
be used as the initial stack pointer register value for the new
thread. These two are not the same except for a machine on which the
stack grows "up" from low memory to high, and on which a
"push" operation first stores the value in memory and then increments
the stack pointer register. Further, on a machine where the
stack grows "down" from high memory to low, interpretation of the
address as the "low memory" address requires a determination
of the intended size of the stack. IEEE\ Std\ 1003.1-2001 has introduced
the new interfaces \fIpthread_attr_setstack\fP() and \fIpthread_attr_getstack\fP()
to resolve these ambiguities.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIpthread_attr_destroy\fP() , \fIpthread_attr_getdetachstate\fP()
, \fIpthread_attr_getstack\fP() , \fIpthread_attr_getstacksize\fP()
, \fIpthread_attr_setstack\fP() , \fIpthread_create\fP() , the
Base Definitions volume of IEEE\ Std\ 1003.1-2001, \fI<limits.h>\fP,
\fI<pthread.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .