Re: Broken makefile given Autoconf version mismatch

[Paul Eggert]

Stepan Kasal <address@hidden> writes:

> --- lib/Automake/FileUtils.pm 2006-04-14 09:25:00.000000000 +0200
> +++ lib/Automake/FileUtils.pm 2006-04-14 09:45:44.000000000 +0200
> @@ -73,6 +73,9 @@
>    $optional = 1
>      if $file_name =~ s/\?$//;
>  
> +  return "-"
> +    if $file_name eq "-";
> +
>    return File::Spec->canonpath ($file_name)
>      if -e $file_name;

I favor this change: it is simple, it restores old functionality,
and it supports useful behavior.

By the way, this general topic has been discussed recently by the Open
Group.  The question was whether standard commands like "od -" are
required to read a file named "-", or whether they are allowed to read
stdin instead.  The consensus was that POSIX does not specify the
behavior here, and that an implementation of "od -" is allowed to
either read a file named "-", or to read standard input.  While this
conclusion doesn't directly affect Automake (which isn't standardized
yet :) it does suggest that "-" should either refer to standard input,
or to a file named "-".  Personally I think the former is more
consistent, as it is the GNU style (used in coreutils).

For more about the Open Group discussion, please see
<http://www.opengroup.org/austin/mailarchives/ag/msg09343.html> and
<http://www.opengroup.org/austin/mailarchives/ag/msg09421.html> (AI-092).