1*2175Sjp161948=pod 2*2175Sjp161948 3*2175Sjp161948=head1 NAME 4*2175Sjp161948 5*2175Sjp161948RAND_load_file, RAND_write_file, RAND_file_name - PRNG seed file 6*2175Sjp161948 7*2175Sjp161948=head1 SYNOPSIS 8*2175Sjp161948 9*2175Sjp161948 #include <openssl/rand.h> 10*2175Sjp161948 11*2175Sjp161948 const char *RAND_file_name(char *buf, size_t num); 12*2175Sjp161948 13*2175Sjp161948 int RAND_load_file(const char *filename, long max_bytes); 14*2175Sjp161948 15*2175Sjp161948 int RAND_write_file(const char *filename); 16*2175Sjp161948 17*2175Sjp161948=head1 DESCRIPTION 18*2175Sjp161948 19*2175Sjp161948RAND_file_name() generates a default path for the random seed 20*2175Sjp161948file. B<buf> points to a buffer of size B<num> in which to store the 21*2175Sjp161948filename. The seed file is $RANDFILE if that environment variable is 22*2175Sjp161948set, $HOME/.rnd otherwise. If $HOME is not set either, or B<num> is 23*2175Sjp161948too small for the path name, an error occurs. 24*2175Sjp161948 25*2175Sjp161948RAND_load_file() reads a number of bytes from file B<filename> and 26*2175Sjp161948adds them to the PRNG. If B<max_bytes> is non-negative, 27*2175Sjp161948up to to B<max_bytes> are read; starting with OpenSSL 0.9.5, 28*2175Sjp161948if B<max_bytes> is -1, the complete file is read. 29*2175Sjp161948 30*2175Sjp161948RAND_write_file() writes a number of random bytes (currently 1024) to 31*2175Sjp161948file B<filename> which can be used to initialize the PRNG by calling 32*2175Sjp161948RAND_load_file() in a later session. 33*2175Sjp161948 34*2175Sjp161948=head1 RETURN VALUES 35*2175Sjp161948 36*2175Sjp161948RAND_load_file() returns the number of bytes read. 37*2175Sjp161948 38*2175Sjp161948RAND_write_file() returns the number of bytes written, and -1 if the 39*2175Sjp161948bytes written were generated without appropriate seed. 40*2175Sjp161948 41*2175Sjp161948RAND_file_name() returns a pointer to B<buf> on success, and NULL on 42*2175Sjp161948error. 43*2175Sjp161948 44*2175Sjp161948=head1 SEE ALSO 45*2175Sjp161948 46*2175Sjp161948L<rand(3)|rand(3)>, L<RAND_add(3)|RAND_add(3)>, L<RAND_cleanup(3)|RAND_cleanup(3)> 47*2175Sjp161948 48*2175Sjp161948=head1 HISTORY 49*2175Sjp161948 50*2175Sjp161948RAND_load_file(), RAND_write_file() and RAND_file_name() are available in 51*2175Sjp161948all versions of SSLeay and OpenSSL. 52*2175Sjp161948 53*2175Sjp161948=cut 54