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BZERO(3)              DragonFly 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)

STANDARDS

The bzero() function conforms to the X/Open System Interfaces option of the IEEE Std 1003.1-2004 (``POSIX.1'') specification. It was removed from the standard in IEEE Std 1003.1-2008 (``POSIX.1''), which recommends using memset(3) instead.

HISTORY

The bzero() function appeared in 4.3BSD. Its prototype existed previously 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 / DragonFly 5.5. DragonFly 5.5 April 11, 2019 DragonFly 5.5

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