diff --git a/steelbox.sh b/steelbox.sh
index df258c3..2470583 100755
--- a/steelbox.sh
+++ b/steelbox.sh
@@ -3,11 +3,23 @@
 
 #!/usr/bin/env bash
 
-version="1.21"
+version="1.31"
 
 echo "Steelbox V$version, Copyright (C) 2022 Kamal Curi"
 echo "Steelbox comes with ABSOLUTELY NO WARRANTY; For license details, read the manual in doc/"
 
+if [ -f /tmp/steelbox.pid ]
+then
+    echo "There is a temporary PID file in /tmp/, which means that"
+    echo "either there's an open instance of steelbox, or it"
+    echo "hasn't properly quit. To avoid manipulating the password"
+    echo "file improperly, steelbox will not open. If you're sure"
+    echo "there are no open steelbox processes, remove"
+    echo "/tmp/steelbox.pid and try again"
+    exit 1
+else
+    echo $$ > steelbox.pid
+fi
 
 if [ -f $HOME/.pasfile.csv.gpg ]
 then
@@ -27,6 +39,8 @@ fi
 
 python3 /opt/steelbox.py $version
 
+rm /tmp/steelbox.pid
+
 gpg -c --no-symkey-cache --cipher-algo AES256 $HOME/.pasfile.csv
 
 if [ $? -gt 0 ]