Hmmm... I would call this a ehm... "cool symlink hack"!! Just an idea though: You may use an actual, existing, file as a target if the system is down for maintenance. So you can put relevant time info in its atime and/or mtime by means of utime. E.g.:

for (my $target=readlink $file) {
    if (-f) {
        warn "System is down for maintenance!\n",
          "Expected to become available again at ",
          scalar localtime +(stat _)[8], "\n";
    } else {
        print "IP address: $_\n";
    }
}

[download]

Of course this is oversimplified and you would put all sorts of checks you think to be appropriate!

All in all the technique is somewhat awkward in that you use file existence to signal failure. But you're already using a "hanging symlink" to carry info, so...

In reply to Re: Cool symlink hack by blazar
in thread Cool symlink hack by grantm

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