X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~webstump/git?p=modbot-mtm.git;a=blobdiff_plain;f=install-substitutions;h=9bcee54da8a0182e7f93432b6408f914ee912735;hp=4f09cd3c06ed52ea06180cba2c6f8f8cbb652d71;hb=ba1a60e8c390874d2fbb484c29d23524e945f934;hpb=fb2fab4c4dcc7ba27dc37e77055c7816a57e3fb5

diff --git a/install-substitutions b/install-substitutions
index 4f09cd3..9bcee54 100755
--- a/install-substitutions
+++ b/install-substitutions
@@ -1,6 +1,16 @@
 #!/bin/bash
 set -e
 
+if [ "x$1" = "x-n" ]; then
+        diffonly=1; diffsparse=0; shift
+elif [ "x$1" = "x-nq" ]; then
+        diffonly=1; diffsparse=1; shift
+else
+        diffonly=0; diffsparse=-1
+fi
+
+if [ $# != 0 ]; then echo >&2 "usage: ./${0##*/} [-n]"; exit 1; fi
+
 . ./get-settings
 
 find -name '*.IN[O1]' ! -path '*/skeleton/*' -exec perl -e '
@@ -27,7 +37,15 @@ find -name '*.IN[O1]' ! -path '*/skeleton/*' -exec perl -e '
 		chmod 0755, $g or die "$g $!";
 	}
 	close F or die $!;
-	if ($overwrite) {
+        if ('$diffonly') {
+                if (!-f $d) {
+                        print "Would create $d\n";
+                } elsif ('$diffsparse' && !$overwrite) {
+                        print "Not reporting on $d as would not overwrite.\n";
+                } else {
+                        system "diff -u $d $g";
+                }
+        } elsif ($overwrite) {
 		rename $g, $d or die "$g $d $!";
 	} else {
 		if (link $g, $d) {