memalign(3) — Linux manual page

memalign(3)              Library Functions Manual             memalign(3)

NAME         top

       memalign - allocate aligned memory

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <malloc.h>

       [[deprecated]] void *memalign(size_t alignment, size_t size);

DESCRIPTION         top

       memalign() is equivalent to aligned_alloc(3), except for the
       CAVEATS documented below.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ memalign()                           │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

VERSIONS         top

       On some systems memalign() is declared in <stdlib.h> instead of
       <malloc.h>.

STANDARDS         top

       None.

HISTORY         top

       glibc 2.0.  SunOS 4.1.3.

CAVEATS         top

       memalign() may not check that the alignment argument is correct.

       Some systems provide no way to reclaim memory allocated with
       memalign() (because one can pass to free(3) only a pointer
       obtained from malloc(3), while, for example, memalign() would call
       malloc(3) and then align the obtained value).  The glibc
       implementation allows memory obtained from memalign() to be
       reclaimed with free(3).

SEE ALSO         top

       aligned_alloc(3)

COLOPHON         top

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Linux man-pages 6.18            2025-12-13                    memalign(3)

Pages that refer to this page: malloc_hook(3),  mtrace(3),  valloc(3)

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