Very simple single port scanner

port.sh

@@ -1 +1,22 @@
-#
+#!/bin/bash
+if [ -z "$1" ]
+then
+    echo "You must specify a filename to read from"
+    exit 1
+fi
+if [ ! -f "$1" ]
+then
+    echo "File $1 does not exist or is not a file"
+    exit 1
+fi
+if [ -z "$2" ]
+then
+	echo "Please, specify a port"
+	exit 1
+fi
+while read ip n
+do
+   nc -z -v -w1 "$ip" "$2"
+
+#   [[ -z "$resolvedIP" ]] && echo "$ip" lookup failure || echo "$ip" resolved to "$resolvedIP"
+done < $1