While this is about file handles, it involves the module Expect. I have been using a log file for Expect and I can specify the logfile with 

$expect->log_file("logfile.log", "w")

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I know the different uses of this, so my question isn't about starting logfiles. I know I can also pass a file handle where I use "logfile.log."

What I'd like to do is read the data that comes in from Expect and is sent out to the logfile in another part of the program, so I can do some work on it. I know there are ways of getting the data, but it would be easier if I could pass Expect a filehandle for the logfile, then, in the other part of the program, just read from that filehandle.

I would love it if I could basically intercept what goes through the filehandle, but if the other routine in the program had to read from it, then write the same text to a file, I could handle that, too.

Is there any way, if a filehandle is used for writing to a file, to read that data in another part of the program as (or after) that data is written to the file?

I considered just reading the file, but it's at least 8K behind what Expect is working on, due to buffers (it's running on Linux, if that makes a difference).

Thanks for any help or thoughts!

In reply to File Handles -- Sharing Output by HalNineThousand

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