Ralf Wildenhues <Ralf.Wildenhues@xxxxxx> writes: > Quoting autoconf.info: > > | `${VAR:-VALUE}' > | Old BSD shells, including the Ultrix `sh', don't accept the colon > | for any shell substitution, and complain and die. > > Can I assume that any shell on a system, which has shared libraries, > understands `${foo:+bar}' and `${foo:-bar}' correctly, even if bar > happens to be `:'? Ultrix had shared libraries, I think; so the answer would probably be 'no' if you want to port to old Ultrix hosts. However these old hosts are becoming pretty rare these days; I'm not sure they're worth worrying about. > Rationale: it makes avoiding a stray colon in colon-separated variables > sooo much easier, In some cases ${foo+bar} and ${foo-bar} suffice; that's portable. _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf