04-13-2011
Quote:
Originally Posted by
disaster
The dd function you posted would actually copy three times a junk of 1024 bytes, ie. 3K bytes in total.
But I understand your question in such a way that you want to read 3 bytes in at once and do that same 300 times, right?
memcpy() is not the right function when you want to store it into a file. You simply need to store 3 bytes in a buffer of char buf[3]; and then use fwrite to write this buffer into a file. Wrap a loop around it so it gets done until 1024bytes are written and you're done
Yes, you are absolutely right!! Thanks a ton for the hint
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LEARN ABOUT REDHAT
rand_file_name
RAND_load_file(3) OpenSSL RAND_load_file(3)
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.
0.9.7a 2001-03-21 RAND_load_file(3)