On Wed, Sep 25, 2013 at 5:59 PM, Glenn Fowler <g...@research.att.com> wrote: > > On Wed, 25 Sep 2013 17:01:06 +0200 Irek Szczesniak wrote: >> On Wed, Sep 25, 2013 at 2:49 PM, Glenn Fowler <g...@research.att.com> wrote: >> > >> > this is just a general comment on those contemplating adding >> > #ifdef to select option visibility based on the underlying system > >> Is this about md5sum(1)? AFAIK the *defaults* are platform-specific, >> based on what Windows does, but not the availability of the options. >> Or is this something different? > > md5sum triggered the comment > but there are / have been other patches in the queue that do similar this > libcmd::sync(1) and ksh93::cd(1) -@ come to mind > I wanted to nip it in the bud so it doesn't become a habit > > now re md5sum > > the gnu docs are fouled up because they don't match gnu-ish reality on cygwin > cygwin actually gets it right by making --binary the default > but that leads to > gnu-md5sum *.tgz > gnu-output > run on linux and cygwin, for the same set of files, producing different > results > the md5sum (should) match but the cygwin output will have the '*' indicator > > suppose, for the same set of *.tgz you do this on cygwin > gnu-md5sum *.tgz > cygwin-output > and this on linux > gnu-md5sum *.tgz > linux-output > on cygwin this will fail > gnu-md5sum --check linux-output > at least on linux this will work > gnu-md5sum --check cygwin-output > > the *ast* --binary default is not platform specific because it is consistent > across unix and _WINIX and honors the principle of least surprise > so this > ast-md5sum *.tgz > ast-output > and this > ast-md5sum --check ast-output > will work no matter what platform either command is executed on > > the next alpha, probably later today to fix the ASTAPI() build problem, will > have libcmd::cksum(1) and libsum fixed to generate and consume the ' ' and '*' > read mode indicators -- the only thing will be that on all systems by default > ast md5sum will print the '*' indicator
Why do you want to do that? On *LINUX* and Solaris 10 with /usr/gnu/bin/mdsum I get this: /usr/bin/md5sum /usr/bin/md5sum 85e85dcf910f4c5d1dd1729b2c81e584 /usr/bin/md5sum /usr/bin/md5sum --binary /usr/bin/md5sum 85e85dcf910f4c5d1dd1729b2c81e584 */usr/bin/md5sum This happens because --text and --binary are identical on Linux and Solaris. > -- lets see how many gnu-reliant scripts > blow up due to that -- this is one of those things that if you demand gnu > semantics on one side prepare to handle them on the other ... nothing to say here. I am not sure whether it is a good idea to serve us that mess GNU coreutils caused and force us to eat it, too. There may be a 3rd option: Use three states: 1. If --binary is given print " *" 2. If --text is given print " : 3. On UNIX/Linux default to " " if no option is given, and default to --text on Windows Irek _______________________________________________ ast-developers mailing list ast-developers@lists.research.att.com http://lists.research.att.com/mailman/listinfo/ast-developers
