pthread_attr_getstack(3p) — Linux manual page



PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The
       Linux implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior),
       or the interface may not be implemented on Linux.

NAME         top

       pthread_attr_getstack, pthread_attr_setstack β€” get and set stack

SYNOPSIS         top

       #include <pthread.h>

       int pthread_attr_getstack(const pthread_attr_t *restrict attr,
           void **restrict stackaddr, size_t *restrict stacksize);
       int pthread_attr_setstack(pthread_attr_t *attr, void *stackaddr,
           size_t stacksize);

DESCRIPTION         top

       The pthread_attr_getstack() and pthread_attr_setstack()
       functions, respectively, shall get and set the thread creation
       stack attributes stackaddr and stacksize in the attr object.

       The stack attributes specify the area of storage to be used for
       the created thread's stack. The base (lowest addressable byte) of
       the storage shall be stackaddr, and the size of the storage shall
       be stacksize bytes. The stacksize shall be at least
       {PTHREAD_STACK_MIN}.  The pthread_attr_setstack() function may
       fail with [EINVAL] if stackaddr does not meet implementation-
       defined alignment requirements.  All pages within the stack
       described by stackaddr and stacksize shall be both readable and
       writable by the thread.

       If the pthread_attr_getstack() function is called before the
       stackaddr attribute has been set, the behavior is unspecified.

       The behavior is undefined if the value specified by the attr
       argument to pthread_attr_getstack() or pthread_attr_setstack()
       does not refer to an initialized thread attributes object.

RETURN VALUE         top

       Upon successful completion, these functions shall return a value
       of 0; otherwise, an error number shall be returned to indicate
       the error.

       The pthread_attr_getstack() function shall store the stack
       attribute values in stackaddr and stacksize if successful.

ERRORS         top

       The pthread_attr_setstack() function shall fail if:

       EINVAL The value of stacksize is less than {PTHREAD_STACK_MIN} or
              exceeds an implementation-defined limit.

       The pthread_attr_setstack() function may fail if:

       EINVAL The value of stackaddr does not have proper alignment to
              be used as a stack, or ((char *)stackaddr + stacksize)
              lacks proper alignment.

       EACCES The stack page(s) described by stackaddr and stacksize are
              not both readable and writable by the thread.

       These functions shall not return an error code of [EINTR].

       The following sections are informative.

EXAMPLES         top



       These functions are appropriate for use by applications in an
       environment where the stack for a thread must be placed in some
       particular region of memory.

       While it might seem that an application could detect stack
       overflow by providing a protected page outside the specified
       stack region, this cannot be done portably. Implementations are
       free to place the thread's initial stack pointer anywhere within
       the specified region to accommodate the machine's stack pointer
       behavior and allocation requirements. Furthermore, on some
       architectures, such as the IA‐64, ``overflow'' might mean that
       two separate stack pointers allocated within the region will
       overlap somewhere in the middle of the region.

       After a successful call to pthread_attr_setstack(), the storage
       area specified by the stackaddr parameter is under the control of
       the implementation, as described in Section 2.9.8, Use of
       Application-Managed Thread Stacks.

       The specification of the stackaddr attribute presents several
       ambiguities that make portable use of these functions impossible.
       For example, the standard allows implementations to impose
       arbitrary alignment requirements on stackaddr.  Applications
       cannot assume that a buffer obtained from malloc() is suitably
       aligned. Note that although the stacksize value passed to
       pthread_attr_setstack() must satisfy alignment requirements, the
       same is not true for pthread_attr_setstacksize() where the
       implementation must increase the specified size if necessary to
       achieve the proper alignment.

RATIONALE         top

       If an implementation detects that the value specified by the attr
       argument to pthread_attr_getstack() or pthread_attr_setstack()
       does not refer to an initialized thread attributes object, it is
       recommended that the function should fail and report an [EINVAL]



SEE ALSO         top

       pthread_attr_destroy(3p), pthread_attr_getdetachstate(3p),
       pthread_attr_getstacksize(3p), pthread_create(3p)

       The Base Definitions volume of POSIX.1‐2017, limits.h(0p),

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 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 .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see .

IEEE/The Open Group               2017            PTHREAD...GETSTACK(3P)

Pages that refer to this page: pthread.h(0p)pthread_attr_setstack(3p)