add a backup for the environment variables named TIMEOUT, QUIT, PORT, HOST

Author: omar-bz

wait-for

@@ -1,5 +1,10 @@
 #!/bin/sh
 
+OLD_TIMEOUT=$TIMEOUT
+OLD_QUIET=$QUIET
+OLD_PORT=$PORT
+OLD_HOST=$HOST
+
 TIMEOUT=15
 QUIET=0
 
@@ -26,7 +31,7 @@ wait_for() {
     result=$?
     if [ $result -eq 0 ] ; then
       if [ $# -gt 0 ] ; then
-        exec "$@"
+        TIMEOUT=$OLD_TIMEOUT QUIET=$OLD_QUIET PORT=$OLD_PORT HOST=$OLD_HOST exec "$@"
       fi
       exit 0
     fi