From owner-freebsd-hackers@FreeBSD.ORG Tue Nov 25 18:56:25 2008 Return-Path: Delivered-To: freebsd-hackers@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A8002106564A for ; Tue, 25 Nov 2008 18:56:25 +0000 (UTC) (envelope-from bf2006a@yahoo.com) Received: from web39102.mail.mud.yahoo.com (web39102.mail.mud.yahoo.com [209.191.86.253]) by mx1.freebsd.org (Postfix) with SMTP id 721F18FC0C for ; Tue, 25 Nov 2008 18:56:25 +0000 (UTC) (envelope-from bf2006a@yahoo.com) Received: (qmail 1708 invoked by uid 60001); 25 Nov 2008 18:56:24 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:Date:From:Reply-To:Subject:To:MIME-Version:Content-Type:Message-ID; b=XhqS++YSfPTPDQKnxFXAFZXGNg7glR7DpqkthAy+cuvr/pR4FouD0XzVs4Gc//eKYK09Z+48kfl1aXnQlcyk+HucdcOCAi5U21Qn7uZRKILZSwYlMh45+vA7obTkQFVms1zHEGMdL4ciMN7dPde0VpgdzHF5sq3FEl+1DuIbjzU=; X-YMail-OSG: b1orZAcVM1nRnmf1mWNaTT73Yb8rLAcnKnoxu.tR05aGy6z7_m17Kp3KSi9qQ242TJJsLVcfM.rcKpOVC6FkM5SMUk.JChiWUa5n5Vl2ph1TDzQ3ed5LPqsO_Kcg2gp2TpumwA-- Received: from [71.233.52.32] by web39102.mail.mud.yahoo.com via HTTP; Tue, 25 Nov 2008 10:56:24 PST X-Mailer: YahooMailWebService/0.7.260.1 Date: Tue, 25 Nov 2008 10:56:24 -0800 (PST) From: bf To: ivoras@FreeBSD.org, freebsd-hackers@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Message-ID: <917783.1650.qm@web39102.mail.mud.yahoo.com> X-Mailman-Approved-At: Tue, 25 Nov 2008 19:23:09 +0000 Cc: Subject: Re: lzma compression/decompression in bsdtar/libarchive? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: bf2006a@yahoo.com List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Nov 2008 18:56:25 -0000 > How useful would LZMA be without supporting the .7z file format? > Probably not at all, since there isn't a gzip-like file format or > wrapper that supports LZMA. ?? Have you looked at this code? Yes, there is: there is an "LZMA compressed file format" and the 7z file format, both of which support LZMA. The former format has been widely adopted by people who distribute lzma-compressed tarballs, especially GNU-related projects that use the lzmautils port. Some projects, like GNU coreutils, no longer distribute the latest versions of their software in bzip2-compressed tarballs. > Since .7z supports a lot of compression formats and options > (unfortunatly saving unix ownership and mode attributes isn't one of > them so be careful there!) it would probably be easier to just import > p7z - and that's probably out of the question. It's available in the > ports just fine. I don't see why the 7z file format couldn't be supported, if that's considered desirable. But it's certainly not *necessary* to do so in order to derive some benefit from lzma compression. It seems to me that importing some form of the smaller lzma sdk would be easier than importing the whole of p7z, which probably isn't necessary in any case. Both the lzma sdk and p7z are available in ports, but they haven't been exploited in ports or the base system. If there is an efficient, integrated lzma (de)compression engine in libarchive, it is almost certain to be more widely used, and that would probably benefit a lot of people. It's the same rationale for having compress, zip, gzip, and bzip2 forms of compression in the base system, although they are also available from ports. Regards, b.