1 files changed, 14 insertions, 0 deletions
diff --git a/examples/functions/isvalidip b/examples/functions/isvalidip
new file mode 100644
index 0000000..0b2dafe
--- /dev/null
+++ b/examples/functions/isvalidip
@@ -0,0 +1,14 @@
+# Thanks to Chris F. A. Johnson <c.f.a.johnson@rogers.com> for this one
+is_validip()
+{
+	case "$*" in
+	""|*[!0-9.]*|*[!0-9]) return 1 ;;
+	esac
+
+	local IFS=.
+	set -- $*
+
+        [ $# -eq 4 ] &&
+	    [ ${1:-666} -le 255 ] && [ ${2:-666} -le 255 ] &&
+	    [ ${3:-666} -le 255 ] && [ ${4:-666} -le 254 ]
+}