A lot of questions here...

"The reason given by the source is..."

Source of what?

It seems to me that picking a (somewhat) arbitrary number to use as a file descriptor, and then dup'ing to that descriptor is a bit risky. How can one be sure that it is not already in use by another process?

I also don't understand the close on exec thing. We've opened a filehandle which holds the output of the echo command. Do filehandles change descriptor numbers midstream somewhere? If it is closing on exec, does that mean it is closing after the echo command has finished executing? If that were true, then it wouldn't do any good to "keep open" after it has already closed.

If the user is already using fd3, then why would it get assigned to the echo command output?

I'm not disputing what you are saying, I just am not understanding why these things are. Your script seems to prove the close on exec thing. I guess one of the things I am wondering is "what exec"?

thanks, Allasso

In reply to Re^4: redirect output from a command to another command by Allasso
in thread redirect output from a command to another command by Allasso

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