bzero(3) — Linux manual page

bzero(3)                 Library Functions Manual                bzero(3)

NAME         top

       bzero - byte-array zero

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <strings.h>  // see memory.h(3head)

       void bzero(size_t n;
                  void a[n], size_t n);

DESCRIPTION         top

       This function writes zeros ('\0') to the memory starting at the
       location pointed to by a.

       It is equivalent to

           memset(a, '\0', n)

RETURN VALUE         top

       None.

ATTRIBUTES         top

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

STANDARDS         top

       None.

HISTORY         top

       4.3BSD.

       Marked as LEGACY in POSIX.1-2001.  Removed in POSIX.1-2008.

CAVEATS         top

       If the compiler deduces that the operation is unnecessary, it may
       totally or partially remove the call.  To ensure the zeroing
       happens regardless of optimizations, use explicit_bzero(3).

SEE ALSO         top

       bstring(3), memory.h(3head), explicit_zero(3), memset(3)

COLOPHON         top

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Linux man-pages 6.19            2026-08-10                       bzero(3)

Pages that refer to this page: explicit_bzero(3),  memory.h(3head),  memset(3),  string_copying(7)

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