dd if=/dev/zero of=file seek=x count=y bs=z conv=notrunc
will overwrite y blocks of z size beginning from block x On Thu, 11 Nov 2010, Matthias Apitz wrote:
Hello, What is the best method to overwrite the blocks of a given file with bytes of 0x00, i.e. not to O_TRUNC away the blocks to the freelist of the file system, but overwrite the old blocks? I've checked $ dd if=/dev/zero of=file count=4 but dd(1) opens the file with O_RDWR|O_CREAT|O_TRUNC which for sure will give away the old blocks and adquire new blocks. Any idea? The background of the question is that I want to make sure, that certain content is not placed into a dump of the file system before give away the output of the dump(8). Thanks matthias -- Matthias Apitz t +49-89-61308 351 - f +49-89-61308 399 - m +49-170-4527211 e <g...@unixarea.de> - w http://www.unixarea.de/ _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
_______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"