bashloggingexecunbuffered-output

bash: force exec'd process to have unbuffered stdout

I've got a script like:

#!/bin/bash
exec /usr/bin/some_binary > /tmp/my.log 2>&1

Problem is that some_binary sends all of its logging to stdout, and buffering makes it so that I only see output in chunks of a few lines. This is annoying when something gets stuck and I need to see what the last line says.

Is there any way to make stdout unbuffered before I do the exec that will affect some_binary so it has more useful logging?

(The wrapper script is only setting a few environment variables before the exec, so a solution in perl or python would also be feasible.)

Solution

  • You might find that the unbuffer script that comes with expect may help.