From The Open Group Base Specifications issue 6, 2004:

#include <strings.h>
void bzero(void *s, size_t n);

• The bzero() function shall place n zero-valued bytes in the area pointed to by s.
• The bzero() function shall not return a value.
• No error are defined.
• Legacy function

The official version of this function has been deprecated. It is not part of the ISO standard, and it is no longer found in recent versions of the POSIX manual.

The following calls are equivalent:

bzero(s, n);
memset(s, 0, n);

Please refer to the memset() page.

• Erasing Sensitive Data - explicit_bzero : GNU Manual.