Dale You might want to look at dd in SUSv3. The wording in SUSv2 is from POSIX 1003.2, and there have been POSIX interpretations in this area and the fixes are in SUSv3. Draft 6 of SUSv3 is now available at http://www.opengroup.org/austin/ (you need to join the Austin Group reflector to get an acct to download the spec). regards Andrew