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POSIX_MEMALIGN(3)        BSD Library Functions Manual        POSIX_MEMALIGN(3)

     posix_memalign -- aligned memory allocation

     #include <stdlib.h>

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

     The posix_memalign() function allocates size bytes of memory such that the allocation's base address is
     an exact multiple of alignment, and returns the allocation in the value pointed to by memptr.

     The requested alignment must be a power of 2 at least as large as sizeof(void *).

     Memory that is allocated via posix_memalign() can be used as an argument in subsequent calls to
     realloc(3), reallocf(3), and free(3).  (Note however, that the allocation returned by realloc(3) or
     reallocf(3) is not guaranteed to preserve the original alignment).

     posix_memalign() should be used judiciously as the algorithm that realizes the alignment constraint can
     incur significant memory overhead.

     The posix_memalign() function returns the value 0 if successful; otherwise it returns an error value.

     The posix_memalign() function will fail if:

     [EINVAL]           The alignment parameter is not a power of 2 at least as large as sizeof(void *).

     [ENOMEM]           Memory allocation error.

     free(3), malloc(3), realloc(3), reallocf(3), valloc(3), malloc_zone_memalign(3)

     The posix_memalign() function conforms to IEEE Std 1003.1-2001 (``POSIX.1'').

BSD                              April 9, 2008                             BSD

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