mcom: commajoin: use awk

The sed solution did not work with OpenBSD sed and Plan9 sed when only
one line was used.

1 files changed, 3 insertions, 1 deletions

diff --git a/mcom b/mcom
index 03823b7..892fee1 100755
--- a/mcom
+++ b/mcom
@@ -2,7 +2,9 @@
 # mcom [TO] - compose mail
 
 commajoin() {
-	sed ':a;N;s/\n/, /;$!b a'
+	awk 'NR==1 {l=$0; next}
+	     {l=l", "$0}
+	     END {print l}'
 }
 
 notmine() {