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bashunixtee

Piping an interactive session to a file

I have made a toy interactive console program that is basically an interpreter:

$ myprogram
> this is user input
this is program output

I want to pipe the full session, both user input and program output, into a log file. I can do this like so:

$ cat | tee >(myprogram | tee -a file.log) >> file.log
> this is user input
this is program output
$ cat file.log
> this is user input
this is program output

So the above session will display to the terminal as usual but will also be duplicated to the log file.

Is there a better way to do this? I don't like how I have to write the log file twice, nor how I have to remember to wipe it before running this command.

Solution

  • The simpler form could be

    tee >(myprogram) | tee -a file.log

    If you want to prevent input being shown again to the screen:

    tee -a file.log | myprogram | tee -a file.log