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BZERO(3)		    Library Functions Manual		      BZERO(3)

NAME
       bzero, explicit_bzero --	write zeroes to	a byte string

LIBRARY
       Standard	C Library (libc, -lc)

SYNOPSIS
       #include	<strings.h>

       void
       bzero(void *b, size_t len);

       void
       explicit_bzero(void *b, size_t len);

DESCRIPTION
       The  bzero() function writes len	zero bytes to the string b.  If	len is
       zero, bzero() does nothing.

       The explicit_bzero() variant behaves the	same, but will not be  removed
       by  a  compiler's  dead	store  optimization pass, making it useful for
       clearing	sensitive memory such as a password.

SEE ALSO
       memset(3), swab(3)

HISTORY
       A bzero() function appeared in 4.3BSD.  Its  prototype  existed	previ-
       ously  in  <string.h>  before  it was moved to <strings.h> for IEEE Std
       1003.1-2001 ("POSIX.1") compliance.

       The  explicit_bzero()  function	first  appeared	 in  OpenBSD  5.5  and
       FreeBSD 11.0.

       IEEE  Std  1003.1-2008 ("POSIX.1") removes the specification of bzero()
       and it is marked	as LEGACY in IEEE Std  1003.1-2004  ("POSIX.1").   For
       portability with	other systems new programs should use memset(3).

FreeBSD	14.3			August 24, 2015			      BZERO(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=explicit_bzero&manpath=FreeBSD+14.3-RELEASE+and+Ports>

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