diff --git a/configure/tools/makeDbDepends.pl b/configure/tools/makeDbDepends.pl
index b989a8661..e35584948 100644
--- a/configure/tools/makeDbDepends.pl
+++ b/configure/tools/makeDbDepends.pl
@@ -2,22 +2,37 @@ eval 'exec perl -S $0 ${1+"$@"}'  # -*- Mode: perl -*-
     if $running_under_some_shell; # makeDbDepends.pl
 
 # Called from within the object directory.
-# Searches the .substitutions files (from the command line) for
-# "file xxx {" entries to create a DEPENDS file
+# Searches the .substitutions file (from the command line) for
+# "file xxx {" entries to create a dependancy output file
 
-open(OUT, ">DBDEPENDS") or die "Cannot open DBDEPENDS: $!";
+sub Usage
+{
+    my ($txt) = @_;
 
-foreach $file (@ARGV) {
-    open(IN, "<$file") or die "Cannot open $file: $!";
-    @substfile = <IN>;
-    close IN or die "Cannot close $file: $!";
+    print "Usage:\n";
+    print "\makeDbDepends dbfile substitutionfile dependsfile\n";
+    print "\nError: $txt\n" if $txt;
 
-    @depends = grep { s/^\s*file\s*(.*)\s*\{.*$/\1/ } @substfile;
-    chomp @depends;
-
-    if (@depends) {
-	$file =~ s/\.substitutions/\.t.db.raw/;
-	print OUT "${file}:: @depends\n";
-    }
+    exit 2;
 }
-close OUT or die "Cannot close $file: $!";
+
+# need at least three args: ARGV[2]
+Usage("need three args") if $#ARGV < 2;
+
+$dbfile = $ARGV[0];
+$subfile = $ARGV[1];
+$outfile = $ARGV[2];
+
+open(OUT, "> $outfile") or die "Cannot open output file $outfile: $!";
+open(IN, "<$subfile") or die "Cannot open $subfile: $!";
+@substfile = <IN>;
+close IN or die "Cannot close $subfile: $!";
+
+@depends = grep { s/^\s*file\s*(.*)\s*\{.*$/\1/ } @substfile;
+chomp @depends;
+
+if (@depends) {
+	$file =~ s/\.substitutions/\.db/;
+	print OUT "${dbfile}:: @depends\n";
+}
+close OUT or die "Cannot close $outfile: $!";