On 01/30/2012 09:10 PM, Eric Blake wrote: > On 01/10/2012 01:15 PM, Mike Frysinger wrote: >> however, if the last argument is just the root path: >> realpath --relative-to=/usr / >> realpath --relative-to=/usr/ / >> we end up with a trailing slash: >> ../ >> >> for consistency, i don't think that should be the case >> >> (reported by Ulrich Müller via https://bugs.gentoo.org/398339) > > Another bug, on a system where // is distinct from /: > > $ realpath --relative-to=/ //machine / // /bin > machine > . > . > bin > $ realpath --relative-to=// //machine / // /bin > machine > . > . > bin > > when it should really be: > > $ realpath --relative-to=/ //machine / // /bin > //machine > . > // > bin > $ realpath --relative-to=// //machine / // /bin > machine > / > . > /bin > > We need to make realpath robust to correct leading // handling; I don't > know if we should follow the lead of 'dirname' in only doing it on > machines where // is special, or if it is easier to make it honor POSIX > by special-casing // everywhere even on machines where / and // are > identical.
So on such a machine, I guess `readlink -m //machine/` outputs '//machine'. To match up with that, I think it makes sense to only do this on systems where a double slash is significant. BTW, this is how I'm interpreting this example: > $ realpath --relative-to=// //machine / // /bin > machine > / > . > /bin I'm taking --relative-to=// to mean relative to "the network". Hence relative output will be machines on the network, while absolute are local paths. gnulib says // matters for Apollo DomainOS (too old to port to), Cygwin, and z/OS. cheers, Pádraig.
