memset(3) — Linux manual page

memset(3)                Library Functions Manual               memset(3)

NAME         top

       memset - fill memory with a constant byte

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <string.h>

       void *memset(size_t n;
                    void s[n], int c, size_t n);

DESCRIPTION         top

       The memset() function fills the first n bytes of the memory area
       pointed to by s with the constant byte c.

RETURN VALUE         top

       The memset() function returns a pointer to the memory area s.

ATTRIBUTES         top

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

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       POSIX.1-2001, C89, SVr4, 4.3BSD.

SEE ALSO         top

       bstring(3), bzero(3), swab(3), wmemset(3)

COLOPHON         top

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Linux man-pages 6.15            2025-06-28                      memset(3)

Pages that refer to this page: mount_setattr(2),  openat2(2),  set_thread_area(2),  bstring(3),  bzero(3),  NULL(3const),  size_t(3type),  void(3type),  wmemset(3),  aio(7),  feature_test_macros(7),  signal-safety(7)

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