=pod =head1 NAME RAND_load_file, RAND_write_file, RAND_file_name - PRNG seed file =head1 SYNOPSIS #include 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); =head1 DESCRIPTION RAND_file_name() generates a default path for the random seed file. B points to a buffer of size B in which to store the filename. On all systems, if the environment variable B is set, its value will be used as the seed file name. Otherwise, the file is called ".rnd", found in platform dependent locations: =over 4 =item On Windows (in order of preference) %HOME%, %USERPROFILE%, %SYSTEMROOT%, C:\ =item On VMS SYS$LOGIN: =item On all other systems $HOME =back If C<$HOME> (on non-Windows and non-VMS system) is not set either, or B is too small for the path name, an error occurs. RAND_load_file() reads a number of bytes from file B and adds them to the PRNG. If B is non-negative, up to B are read; if B is -1, the complete file is read. RAND_write_file() writes a number of random bytes (currently 1024) to file B which can be used to initialize the PRNG by calling RAND_load_file() in a later session. =head1 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 B on success, and NULL on error. =head1 SEE ALSO L, L, L =head1 COPYRIGHT Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. Licensed under the OpenSSL license (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at L. =cut