NAME
	file_size - return size of file

SYNOPSIS
	int file_size(string path)


DESCRIPTION
	This function will return size of the file at path. If this_object()
	does not have access to the file or it doesn't exist, -1 is
	returned. If the path points to a directory, the returnvalue will
	be -2.

SEE ALSO
	efun/get_files, kfun/get_dir