Simultaneously Calling Multiple External Programs

[saeden]

Howdy! I'm stuck and I'm hoping someone can point me in the right direction.

I have a php script which when executed calls an external program. The external program goes off and figures some things out and the output of the program is returned as as an array to the calling PHP program.

Next a second external program is called and the process is repeated.

This goes on for 4 external program calls. The arrays are then analyzed and the results are outputted.

Since the 4 external programs are independent of each other but each takes 3 - 5 minutes to run, I would like to run them all at the same time and then, when they are all done, proceed with the rest of the analysis.

The problem is that I am stuck on how to make the above work or if it's even possible. Any suggestions would be appreciated.

Thanks,

Scott A. Eden

[sarahk]

Most scripts will timeout when having to run for 4 or 5 minutes. You might be better to run them via a cron job and store the result and have a final process that gets the results - checks they are current - and collates the final answer.

To run the jobs at the same time from the same script you need to be able to fork. Fork isn't available in php4 but there is a script called phpFork which simulates that. See http://www.phpclasses.org/browse/file/4017.html

[bradgrafelman]

sarahk wrote:

you need to be able to fork

If your webhost is on a Unix-type O/S, forking can be done at the CLI by adding an ampersand at the end:

exec('/path/to/program &');