PTHREAD_ATTR_GETSTACK(P) POSIX Programmer's Manual PTHREAD_ATTR_GETSTACK(P) NAME pthread_attr_getstack, pthread_attr_setstack - get and set stack attributes SYNOPSIS #include 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 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 stor- age shall be stackaddr, and the size of the storage shall be stacksize bytes. The stacksize shall be at least {PTHREAD_STACK_MIN}. The stack- addr shall be aligned appropriately to be used as a stack; for example, pthread_attr_setstack() may fail with [EINVAL] if ( stackaddr & 0x7) is not 0. All pages within the stack described by stackaddr and stacksize shall be both readable and writable by the thread. RETURN VALUE 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 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 if ( stackaddr + stacksize) lacks proper align- ment. 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 None. APPLICATION USAGE These functions are appropriate for use by applications in an environ- ment 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 accommo- date 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. RATIONALE None. FUTURE DIRECTIONS None. SEE ALSO pthread_attr_init() , pthread_attr_setdetachstate() , pthread_attr_set- stacksize() , pthread_create() , the Base Definitions volume of IEEE Std 1003.1-2001, , 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 . IEEE/The Open Group 2003 PTHREAD_ATTR_GETSTACK(P)