diff --git a/pbatch/pb.rb b/pbatch/pb.rb
index c5f9f7f..61ac495 100755
--- a/pbatch/pb.rb
+++ b/pbatch/pb.rb
@@ -79,24 +79,34 @@ end
 
 def increasejobscounter
 	jobscounter = 0
-	if File.exists(COUNTERFILE)
-		File.new(COUNTERFILE, "r+").flock(File::LOCK_EX){|file|
-			jobscounter = file.read.to_i
+	if FileTest.exists?(COUNTERFILE)
+		File.new(COUNTERFILE).flock(File::LOCK_EX)
+		File.open(COUNTERFILE, "r+"){|file|
+			jobscounter = file.read
+			if jobscounter.empty?
+				jobscounter = 0
+			end
+			jobscounter = jobscounter.to_i
 			jobscounter += 1
 			file.seek(0)
 			file.puts jobscounter
 		}
+		File.new(COUNTERFILE, "r+").flock(File::LOCK_UN)
 	else
-		File.new(COUNTERFILE, "w").flock(File::LOCK_EX){|file|
+		File.open(COUNTERFILE, "w"){|file|
+			File.new(COUNTERFILE).flock(File::LOCK_EX)
 			jobscounter = 1
 			file.puts jobscounter
 		}
+		File.new(COUNTERFILE, "r+").flock(File::LOCK_UN)
 	end
 	return jobscounter
 end
 
 def addjob
 	p ARGV.join(" ")
+	jobnumber=sprintf("%06d", increasejobscounter)
+	p jobnumber
 end
 
 def addjobfromfile