So you want one process to pay attention to what a completely independent process is dong while the 'watching process' keeps its back turned and eyes closed so as to speak. As the processes are independent you will have to poll/signal somehow or other. Your options would include

  • writing the watching process pid to a file and having the updating process send a signal to it when it does the update.
  • forking off a child from the watching process to do guard duty.
  • Polling an ENV var/ lockfile / database periodically from the watching process where the updating process leaves its mark
  • Polling the file update time for the config file.
  • Alternatively you could just get your watcher to re-read the config file every X minutes and just accept that updates will be sub dynamic. If the config is small this will have next to no overhead and is probably the simplest to implement (ask Microsoft :0)
  • Finally the updating process could outright kill the watcher and fork off a new re-initialized one

    All of these approaches are used. There are no doubt others.

    cheers

    tachyon

    s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

    In reply to Re: How can I alert perl to a file write by tachyon
    in thread How can I alert perl to a file write by Anonymous Monk

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