Re: CVS commit: pkgsrc/lang/perl5/files

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Sun, 14 Feb 2010 15:12:37 +0000
    From:        Matthias Scheler <tron%NetBSD.org@localhost>
    Message-ID:  <20100214151237.GA29439%colwyn.zhadum.org.uk@localhost>

  | I'm not convinced that ": ${PKG_PREFIX=@PREFIX@}" is understood by
  | every bourne-like shell.

While bugs anywhere are possible, of course, that one should be OK,
the 5 basic variable substitutions $(X) $(X-Y) ${X=Y} ${X+Y} and ${X?Y}
were in the original Bourne shell (the 7th edition /bin/sh), and should
work everywhere.   At the minute I'm not as sure that the ':' variants
were in the first version, but these days I'd be very surprised to find
anything pretending to be a Bourne compatible shell that didn't handle
all of those.   Similarly the ':' command has been there since the beginning,
and using it that way (for side effects of arg evaluation) has been an
idiom since then.

kre