RAND_load_file, RAND_write_file, RAND_file_name - PRNG seed file
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 );
The RAND_load_file() function reads a number of bytes from file file‐
name and adds them to the PRNG. If max_bytes is non-negative, up to
max_bytes are read; starting with OpenSSL 0.9.5, if max_bytes is -1,
the complete file is read.
The RAND_write_file() function writes a number of random bytes (cur‐
rently 1024) to file filename which can be used to initialize the PRNG
by calling RAND_load_file() in a later session.
The RAND_file_name() function 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.
The RAND_load_file() function returns the number of bytes read.
The RAND_write_file() function returns the number of bytes written, and
-1 if the bytes written were generated without appropriate seed.
The RAND_file_name() function returns a pointer to buf on success, and
NULL on error.
The RAND_load_file(), RAND_write_file(), and RAND_file_name() functions
are available in all versions of SSLeay and OpenSSL.
Functions: rand_ssl(3), RAND_add(3), RAND_cleanup(3)RAND_load_file(3)