Does anyone know a mean of putting a 'time' command before every command in a bash session?
Sorry for the wrong answer before, I missunderstood your question.
To have the time added before every command that you execute on the shell you can do something like this
This will rebind the return key. Now every time you press return instead of writing a newline \n it will go to the beginning of the line, enter the text 'time' and a space, go to the end of the line and enter the newline \n thereby producing the desired effect.
If you don't want to sacrifice your Enter Key you could make a 'second' benchmark-enter Key like F12 by binding the command like this
Now instead of replacing the return key you bound F12.
The background of all this is that bash uses GNU readline to read commands. So readline would be a good starting point for further command manipulation, etc.
I realize that this is outside of the scope of this question but...
Every command that takes longer than 5 seconds (I'm pretty sure) will display the output of
Include \t in your prompt string. It will include the time in your prompt at the point where you include it. See: http://www.ibm.com/developerworks/linux/library/l-tip-prompt/