valloc(3) — Linux manual page

valloc(3)                Library Functions Manual               valloc(3)

NAME         top

       valloc - page-aligned memory allocation

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <stdlib.h>

       [[deprecated]] void *valloc(size_t size);

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

       valloc():
           Since glibc 2.12:
               (_XOPEN_SOURCE >= 500) && !(_POSIX_C_SOURCE >= 200112L)
                   || /* glibc >= 2.19: */ _DEFAULT_SOURCE
                   || /* glibc <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE
           Before glibc 2.12:
               _BSD_SOURCE || _XOPEN_SOURCE >= 500

DESCRIPTION         top

       valloc() allocates size bytes and returns a pointer to the
       allocated memory.  The memory address will be a multiple of the
       page size.

       It is equivalent to memalign(sysconf(_SC_PAGESIZE),size).

ATTRIBUTES         top

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

VERSIONS         top

       According to SUSv2, valloc() is declared in <stdlib.h>.  glibc
       declares it in <malloc.h>, and also in <stdlib.h> if suitable
       feature test macros are defined (see above).

STANDARDS         top

       BSD, GNU.

HISTORY         top

       glibc 2.0.  3.0BSD.  Documented as obsolete in 4.3BSD, and as
       legacy in SUSv2.

CAVEATS         top

       See memalign(3).

SEE ALSO         top

       memalign(3)

COLOPHON         top

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

Pages that refer to this page: pvalloc(3)

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