Add a function to get an available random port
This commit adds a new function get_random_port to return a randomly
available port from the local port range.
Change-Id: Icaed180cc14602a74cdb3fd3456b690d8a4c729c
diff --git a/functions b/functions
index 52a82fa..4d2703f 100644
--- a/functions
+++ b/functions
@@ -732,6 +732,24 @@
sudo systemctl daemon-reload
}
+# Get a random port from the local port range
+#
+# This function returns an available port in the local port range. The search
+# order is not truly random, but should be considered a random value by the
+# user because it depends on the state of your local system.
+function get_random_port {
+ read lower_port upper_port < /proc/sys/net/ipv4/ip_local_port_range
+ while true; do
+ for (( port = upper_port ; port >= lower_port ; port-- )); do
+ sudo lsof -i ":$port" &> /dev/null
+ if [[ $? > 0 ]] ; then
+ break 2
+ fi
+ done
+ done
+ echo $port
+}
+
# Restore xtrace
$_XTRACE_FUNCTIONS