POSIX_MEMALIGN(3)          POSIX Programmer's Manual         POSIX_MEMALIGN(3)



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


NAME
       posix_memalign -- aligned memory allocation (ADVANCED REALTIME)

SYNOPSIS
       #include <stdlib.h>

       int posix_memalign(void **memptr, size_t alignment, size_t size);

DESCRIPTION
       The posix__memalign() function shall allocate size bytes aligned on a
       boundary specified by alignment, and shall return a pointer to the
       allocated memory in memptr.  The value of alignment shall be a power of
       two multiple of sizeof(void **).

       Upon successful completion, the value pointed to by memptr shall be a
       multiple of alignment.

       If the size of the space requested is 0, the behavior is
       implementation-defined; the value returned in memptr shall be either a
       null pointer or a unique pointer.

       The free() function shall deallocate memory that has previously been
       allocated by posix__memalign().

RETURN VALUE
       Upon successful completion, posix__memalign() shall return zero;
       otherwise, an error number shall be returned to indicate the error.

ERRORS
       The posix__memalign() function shall fail if:

       EINVAL The value of the alignment parameter is not a power of two
              multiple of sizeof(void **).

       ENOMEM There is insufficient memory available with the requested
              alignment.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The posix__memalign() function is part of the Advisory Information
       option and need not be provided on all implementations.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       free(), malloc()

       The Base Definitions volume of POSIX.1-2008, <stdlib.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is
       POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html .

       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
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2013                    POSIX_MEMALIGN(3)
