Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!think!snorkelwacker!paperboy!meissner From: meissner@osf.org (Michael Meissner) Newsgroups: comp.unix.wizards Subject: Re: make -b does what? Message-ID: Date: 23 Feb 90 15:54:06 GMT References: <5980062@hpfcdc.HP.COM> <1990Feb22.042021.4936@phri.nyu.edu> <23@ctbilbo.UUCP> Sender: news@OSF.ORG Organization: Open Software Foundation Lines: 34 In-reply-to: ray@ctbilbo.UUCP's message of 23 Feb 90 00:25:27 GMT In article <23@ctbilbo.UUCP> ray@ctbilbo.UUCP (Ray Ward) writes: | In article <1990Feb22.042021.4936@phri.nyu.edu> roy@phri.nyu.edu (Roy Smith) writes: | >lois@hpfcdc.HP.COM (Lois Gerber) writes: | >> This question is directed at OLD (and I mean OLD) Unix gurus : | >> Can anyone explain to me clearly what the -b option is for in make? | > Beats the hell out of me. I can't even find make in my (6th | >edition) Unix manual at all. Did I get a defective manual? | | I would suspect the -b came in somewhere around System III. Steve Talbott's | _Managing Projects with Make_ ( O'Reilly and Assoc. 1-800-338-NUTS ) | describes the option: | | The -b option is, in most implementations, on by default. It | assures backward compatibility with earlier versions of _make_, | so that old description files continue to work. | | I have no idea what the old description file format differences were. In practice, -b serves another use. If you have recursive makefiles, you usually use (on System V) something like: dir/foo: dir/foo.c cd dir; $(MAKE) -$(MAKEFLAGS) foo If no arguments were passed to the toplevel make, then the recursive make would get a plain "-", which means that the Makefile is passed via standard input. Since -b is implicitly set, it is passed on to the recursive make. -- Michael Meissner email: meissner@osf.org phone: 617-621-8861 Open Software Foundation, 11 Cambridge Center, Cambridge, MA Catproof is an oxymoron, Childproof is nearly so