I think that a simple solution could be to have a process handle file. Do the following:

Create a text file, with six lines, each containing the word HANDLE.

Next, when your script executes, it should:

* Lock the handle file.
* Open the handle file.
* Read in the handle file.
* If there are no "HANDLE"s left, exit.
* If there are "HANDLE"s left, pop one off the bottom of the file.
* Write out the file.
* Close it.
* Unlock it.

Then do whatever work you intended to do within the script. Upon completion of the work, do the following:

* Lock and open the HANDLE file.
* Push your HANDLE back into the end of the file.
* Close and unlock the file.
* exit.

Oh, and if it finds HANDLE file already locked, just wait a second and try again.

It's a pretty simple method. If you want to increase or decrease the number of simultaneous processes, you just alter the number of handles in the file. ...the file could just as easily contain a counter number instead of a series of "handles". Each process decrements the counter, runs, then increments the counter. If the counter ever hits zero, no more processes can run. Same basic concept.

Dave

"If I had my life to do over again, I'd be a plumber." -- Albert Einstein