Use check for defined value after eval(), style fixes, fix typo in sub name and var name

confcheck.pl

@@ -12,7 +12,7 @@ use JSON::PP;
 use version; our $VERSION = qw (1.0);
 
 my $c = 'data/config.json';
-open (my $C, '<', $c) || die "No conf at $c: $OS_ERROR\n"; ## no critic (InputOutput::RequireBriefOpen)
+open (my $C, '<', $c) || die "No conf at $c: $OS_ERROR\n";
 my $len = (stat $c) [7];
 my $json;
 my $readlen = read ($C, $json, $len);