It seems you don't need any communication from the ftp downloader back to the query/main program and more than one ftp download might get started simultaneously without any dire consequences (except maybe if it is the same file to download. If that's a problem, downloader.pl might use a lockfile or download to a randomly generated name and do a rename after download is complete). So the easiest solution is to start a separate program which does the ftp download and gets its data simply over the command line:

while($query=getnewquery())
  #database query
  ...
  $filename= ...
  # start the download
  system("downloader.pl $filename &") or print "failure to start downl
+oader.pl\n";
}

[download]
The '&' starts the downloader.pl program in the background so it is executed in parallel. Depending on the ftp download downloader.pl might be substituted with the actual ftp command.

In reply to Re: Threading - Conceptual Question About Use Of Array by jethro
in thread Threading - Conceptual Question About Use Of Array by ~~David~~

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