only add user or group if not already existing

1 files changed, 15 insertions, 13 deletions

diff --git a/add-group b/add-group
index 2867c90..ea9e920 100755
--- a/add-group
+++ b/add-group
@@ -20,21 +20,23 @@ num=$2				# number of packages installed
 name=$3				# name of the group
 users=$4			# users to add to this group
 
-/usr/sbin/groupadd -r $name > /dev/null
+if ! getent group $name /dev/null 2>&1; then
+    /usr/sbin/groupadd -r $name > /dev/null
 
-if [ -n "$users" ]; then
-    SAVED_IFS="$IFS"
-    export IFS="$IFS",
-    set $users
-    IFS="$SAVED_IFS"
+    if [ -n "$users" ]; then
+	SAVED_IFS="$IFS"
+	export IFS="$IFS",
+	set $users
+	IFS="$SAVED_IFS"
 
-    for u in $*; do
-	old=`egrep "[:,]$u(,|$)" /etc/group | cut -d : -f 1 | xargs echo`
-	if [ -n "$old" ]; then
-	    old=`echo ",$old" | sed 's/ /,/g'`
-	fi
-	/usr/sbin/usermod -G $name$old $u > /dev/null
-    done
+	for u in $*; do
+	    old=`egrep "[:,]$u(,|$)" /etc/group | cut -d : -f 1 | xargs echo`
+	    if [ -n "$old" ]; then
+		old=`echo ",$old" | sed 's/ /,/g'`
+	    fi
+	    /usr/sbin/usermod -G $name$old $u > /dev/null
+	done
+    fi
 fi
 
 exit 0