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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(const 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

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  location 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, respec-
     tively.

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  stack-
            addr + stacksize is not suitably aligned.

     POSIX.1  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.

ATTRIBUTES

     For   an   explanation   of   the  terms  used  in  this  section,  see
     attributes(7).

     +-------------------------+---------------+---------+
     |Interface                | Attribute     | Value   |
     +-------------------------+---------------+---------+
     |pthread_attr_setstack(), | Thread safety | MT-Safe |
     |pthread_attr_getstack()  |               |         |
     +-------------------------+---------------+---------+

CONFORMING TO

     POSIX.1-2001, POSIX.1-2008.

NOTES

     These  functions  are provided for applications that must ensure that a
     thread's stack is placed in a particular location.  For  most  applica-
     tions,  this is not necessary, and the use of these functions should be
     avoided.  (Use pthread_attr_setstacksize(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 neces-
     sary, it is the application's responsibility to allocate a  guard  area
     (one or more pages protected against reading and writing) to handle the
     possibility 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);  other-
     wise,  the  threads  will attempt to use the same memory area for their
     stacks, and chaos will ensue.

EXAMPLE

     See pthread_attr_init(3).