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MEMSET(3)                  Library Functions Manual                  MEMSET(3)

NAME
     memset - write a byte to byte string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <string.h>

     void *
     memset(void *b, int c, size_t len);

DESCRIPTION
     The memset() function writes len bytes of value c (converted to an
     unsigned char) to the string b.

RETURN VALUES
     The memset() function returns the original value of b.

     Note that the compiler may optimize away a call to memset() if it can
     prove that the string will not be used by the program again, for example
     if it is allocated on the stack and about to go out of scope.  If you
     want to guarantee that zeros are written to memory, for example to
     sanitize a buffer holding a cryptographic secret, use explicit_memset(3).

SEE ALSO
     bzero(3), explicit_memset(3), swab(3)

STANDARDS
     The memset() function conforms to ANSI X3.159-1989 ("ANSI C89").

NetBSD 10.99                     June 23, 2013                    NetBSD 10.99