RAND_load_file(3ssl)
NAME
RAND_load_file, RAND_write_file, RAND_file_name - PRNG seed file
SYNOPSIS
#include <openssl/rand.h> const char *RAND_file_name(char *buf, size_t num); int RAND_load_file(const char *filename, long max_bytes); int RAND_write_file(const char *filename);
DESCRIPTION
RAND_file_name() generates a default path for the random seed file. buf
points to a buffer of size num in which to store the filename. The seed
file is $RANDFILE if that environment variable is set, $HOME/.rnd
otherwise. If $HOME is not set either, or num is too small for the path
name, an error occurs.
RAND_load_file() reads a number of bytes from file filename and adds
them to the PRNG. If max_bytes is non-negative, up to to max_bytes are
read; starting with OpenSSL 0.9.5, if max_bytes is -1, the complete
file is read.
RAND_write_file() writes a number of random bytes (currently 1024) to
file filename which can be used to initialize the PRNG by calling
RAND_load_file() in a later session.
RETURN VALUES
RAND_load_file() returns the number of bytes read.
RAND_write_file() returns the number of bytes written, and -1 if the
bytes written were generated without appropriate seed.
RAND_file_name() returns a pointer to buf on success, and NULL on
error.
SEE ALSO
rand(3), RAND_add(3), RAND_cleanup(3)
HISTORY
- RAND_load_file(), RAND_write_file() and RAND_file_name() are available
in all versions of SSLeay and OpenSSL.