Add new service "file_tracker"

This new service periodically tracks the file open in the system.

Closes-Bug: #1995502
Change-Id: I02e097fef07655ff571af9f35bf258b2ed975098
diff --git a/tools/file_tracker.sh b/tools/file_tracker.sh
new file mode 100755
index 0000000..9c31b30
--- /dev/null
+++ b/tools/file_tracker.sh
@@ -0,0 +1,47 @@
+#!/bin/bash
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+set -o errexit
+
+# time to sleep between checks
+SLEEP_TIME=20
+
+function tracker {
+    echo "Number of open files | Number of open files not in use | Maximum number of files allowed to be opened"
+    while true; do
+        cat /proc/sys/fs/file-nr
+        sleep $SLEEP_TIME
+    done
+}
+
+function usage {
+    echo "Usage: $0 [-x] [-s N]" 1>&2
+    exit 1
+}
+
+while getopts ":s:x" opt; do
+    case $opt in
+        s)
+            SLEEP_TIME=$OPTARG
+            ;;
+        x)
+            set -o xtrace
+            ;;
+        *)
+            usage
+            ;;
+    esac
+done
+
+tracker