10.15. Cutting and Pasting the Prompt

This one is weird but cool. Rory Toma wrote to suggest a prompt like this: : rory@demon ; . How is this useful? You can triple click on any previous command (in Linux, anyway) to highlight the whole line, then paste that line in front of another prompt and the stuff between the ":" and the """ is ignored, like so:

: rory@demon ; uptime
  5:15pm  up 6 days, 23:04,  2 users,  load average: 0.00, 0.00, 0.00
: rory@demon ; : rory@demon ; uptime
  5:15pm  up 6 days, 23:04,  2 users,  load average: 0.00, 0.00, 0.00

The prompt is a no-op, and if your PS2 is set to a space, multiple lines can be cut and pasted as well.

Diego Puppin sent in another bizarre but useful variant: export PS1="cd \w; ". With your prompt set like this, cutting and pasting a previous command line with prompt means that you automatically cd to the proper directory before executing the command. "This is useful, for instance, to track your operations in a complex build tree."