getopt on Linux by default re-orders arguments.

Stop it. This broke tests that had "-1" on the command line as argument.

regress/NiHTest.pm

diff --git a/regress/NiHTest.pm b/regress/NiHTest.pm
index e8b1db7..b2af114 100644
--- a/regress/NiHTest.pm
+++ b/regress/NiHTest.pm
@@ -265,6 +265,7 @@
 
 	$ENV{TZ} = "UTC";
 	$ENV{LC_CTYPE} = "C";
+	$ENV{POSIXLY_CORRECT} = 1;
 	$self->sandbox_create($tag);
 	$self->sandbox_enter();