How to write to a file and, while the file is still being writen, read and parse its contents using

Posted by Isabelle on Server Fault See other posts from Server Fault or by Isabelle
Published on 2010-03-17T10:48:14Z Indexed on 2010/03/17 10:51 UTC
Read the original article Hit count: 257

Filed under:

shell

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script

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files

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redhat

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redirection

Hello.

I'm actually trying to write a shell script that logs the output of a command to a file but, since the command takes a long time to complete (about 15 minutes), I would like to start parsing the output of the command (content of the file) before the command is completed, so I can send messages to the standard output (the user), like:

10% complete
45% complete

and so on.

Program steps

Redirect command to a file: $(command) > $FILE
Start reading and parsing the output ($FILE) before the command is finished.

I thought of using pararell programming, but I havent't got the hang of it.

Any help you be appreciated.

Best regards.

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