This is more of a design flaw than a bug.  In C the fread() function returns the number of bytes read.  In php it returns the string read.  The C version is better.  If you are reading binary data from a remote HTTP source and you need to know how much data you have read it is impossible with the PHP version.  You cant read in a chunk then do a strlen() on the chunk because its binary and may contain null chars.  read() seems to have the right interface but its experimental and only for sockets.