PTHREAD_ATTR_SETSTACK(3)                            Linux Programmer's Manual                           PTHREAD_ATTR_SETSTACK(3)



NAME
       pthread_attr_setstack, pthread_attr_getstack - set/get stack attributes in thread attributes object

SYNOPSIS
       #include <pthread.h>

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

       Compile and link with -pthread.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       pthread_attr_getstack(), pthread_attr_setstack(): _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600

DESCRIPTION
       The  pthread_attr_setstack()  function  sets  the stack address and stack size attributes of the thread attributes object
       referred to by attr to the values specified in stackaddr and stacksize, respectively.  These attributes specify the loca-
       tion and size of the stack that should be used by a thread that is created using the thread attributes object attr.

       stackaddr  should  point  to the lowest addressable byte of a buffer of stacksize bytes that was allocated by the caller.
       The pages of the allocated buffer should be both readable and writable.

       The pthread_attr_getstack() function returns the stack address and stack size attributes of the thread attributes  object
       referred to by attr in the buffers pointed to by stackaddr and stacksize, respectively.

RETURN VALUE
       On success, these functions return 0; on error, they return a nonzero error number.

ERRORS
       pthread_attr_setstack() can fail with the following error:

       EINVAL stacksize  is  less than PTHREAD_STACK_MIN (16384) bytes.  On some systems, this error may also occur if stackaddr
              or stackaddr + stacksize is not suitably aligned.

       POSIX.1-2001 also documents an EACCES error if the stack area described by stackaddr and stacksize is not  both  readable
       and writable by the caller.

VERSIONS
       These functions are provided by glibc since version 2.2.

CONFORMING TO
       POSIX.1-2001.

NOTES
       These  functions are provided for applications that must ensure that a thread's stack is placed in a particular location.
       For most applications, this is not necessary, and the use of these functions should be avoided.   (Use  pthread_attr_set-
       stacksize(3) if an application simply requires a stack size other than the default.)

       When an application employs pthread_attr_setstack(), it takes over the responsibility of allocating the stack.  Any guard
       size value that was set using pthread_attr_setguardsize(3) is ignored.  If deemed  necessary,  it  is  the  application's
       responsibility to allocate a guard area (one or more pages protected against reading and writing) to handle the possibil-
       ity of stack overflow.

       The address specified in stackaddr should be suitably aligned:  for  full  portability,  align  it  on  a  page  boundary
       (sysconf(_SC_PAGESIZE)).   posix_memalign(3) may be useful for allocation.  Probably, stacksize should also be a multiple
       of the system page size.

       If attr is used to create multiple threads, then the caller must change the stack  address  attribute  between  calls  to
       pthread_create(3);  otherwise,  the  threads  will  attempt  to use the same memory area for their stacks, and chaos will
       ensue.

EXAMPLE
       See pthread_attr_init(3).

SEE ALSO
       mmap(2),  mprotect(2),  posix_memalign(3),  pthread_attr_init(3),  pthread_attr_setguardsize(3),   pthread_attr_setstack-
       addr(3), pthread_attr_setstacksize(3), pthread_create(3), pthreads(7)

COLOPHON
       This  page  is  part of release 3.25 of the Linux man-pages project.  A description of the project, and information about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



Linux                                                      2008-10-24                                   PTHREAD_ATTR_SETSTACK(3)