<p>Compiling with mawk 'make install' failes with:</p>

<p>NP_VERSION=1.5.110.g2d494 mawk -f ./subst check_mailq.pl > check_mailq<br>
mawk: run time error: regular expression compile failed (missing operand)<br>
/var/lib/postfix' || -d '/var/local/lib/postfix<br>
        FILENAME="check_mailq.pl" FNR=614 NR=614<br>
make[1]: *** [check_mailq] Error 2<br>
make[1]: Leaving directory `/home/holger/src/monitoring-plugins/plugins-scripts'<br>
make: *** [install-recursive] Error 1</p>

<p>The problem seems:</p>

<p><a href="https://github.com/monitoring-plugins/monitoring-plugins/blob/2d49468a2533c4623d4121ee0e12260bcba78905/plugins-scripts/subst.in#L43">https://github.com/monitoring-plugins/monitoring-plugins/blob/2d49468a2533c4623d4121ee0e12260bcba78905/plugins-scripts/subst.in#L43</a></p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br><a href='https://github.com/monitoring-plugins/monitoring-plugins/pull/1242#issuecomment-36288975'>Reply to this email on GitHub</a>.<img src='https://github.com/notifications/beacon/5514713__eyJzY29wZSI6Ik5ld3NpZXM6QmVhY29uIiwiZXhwaXJlcyI6MTcwOTA2NjYyNiwiZGF0YSI6eyJpZCI6MjY2MTg4MTV9fQ==--5a66aecfd9023265af20bf70aa8ce719aca34d34.gif' height='1' width='1'></p>