As a solution to recording terminal output into a log file, whilst still viewing output on the terminal (using code within a bash script itself rather than piping to tee on the command-line) I typically use:

exec > >(tee "$DIR/Logs/System.log")

Near the top of the bash script.

This bash script eventually invokes a Perl script. Output printed to the terminal comes from both Bash and Perl, however, the inclusion of the above line causes the buffering of the Perl-specific portion of the output such that it's only displayed on the terminal once the script fully completes. Running the Perl script as a standalone provides the intended real-time updates, as does invoking it via Bash without the above line.

Could anybody explain why this is happening and also suggest a solution? The ultimate goal here is to provide real-time feedback to the user on the terminal, whilst keeping a hard-copy of this feedback in a log file.

In reply to Printing to STDOUT buffered when invoking Perl within a bash-script using tee by TJCooper

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