Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ucbvax!husc6!ut-sally!std-unix From: std-unix@ut-sally.UUCP Newsgroups: comp.std.unix Subject: Re: tar vs. cpio Message-ID: <8199@ut-sally.UUCP> Date: Tue, 2-Jun-87 14:35:19 EDT Article-I.D.: ut-sally.8199 Posted: Tue Jun 2 14:35:19 1987 Date-Received: Sat, 6-Jun-87 09:44:37 EDT Sender: std-unix@ut-sally.UUCP Reply-To: guy@sun.com (Guy Harris) Lines: 53 Approved: jsq@sally.utexas.edu (Moderator, John Quarterman) From: guy@sun.com (Guy Harris) I agree with the proposal; these are just some nits. ...meeting to drop sS10.1 altogether... The sequence "s^HS" appears here, and in several other places - is this intentional or a bizarre result from "nroff"? [ It's nroff's attempt to produce a section sign. The actual note will be formatted with troff, which can handle it. I will incorporate your other comments. -mod ] 4. Hard links are not handled well, since cpio format does not record that two files are linked. If two files that are linked are written in cpio format, two copies will be written. There is an option to the cpio program to detect duplicate files by matching pairs of (h_dev, h_ino) and producing links, but that is done after the fact. Actually, this is the standard way "cpio" handles hard links; it's not an option. 5. Symbolic links are not handled at all, and no type value is reserved for them. This makes cpio useless on a large class of historical implementations (those based on 4.2BSD or its file system) for one of the main purposes of POSIX sS10.1: archiving files for later retrieval and use on the same system. (Another s^HS here) It is possible to extend this format to handle symbolic links; we have done this. [ But remember that what was proposed to P1003.1 was existing System V cpio format. -mod ] ...However, cpio was not available outside AT&T before the release of System III, while tar was in wide use with Version 7 and is still much more common. Actually, the old "cpio" was available with PWB/UNIX 1.0, which AT&T did release. Also, it appears that the cpio format of PWB was not the same as that of System III. Although System III and perhaps early releases of System V did not include tar, current releases of System V do. No, System III and all releases of S5 included "tar". Volume-Number: Volume 11, Number 45