Talk:Bash/Prompt customization

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Revision as of 20:36, 9 February 2010 by Bkerin (Talk | contribs) (fixing the bugs in the return value visualization)

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The return value visualization stuff didn't quite work right for me. The command history prints out funny (bits of old command prefixes stay displayed), and also long lines behaved oddly (wrapped back to start etc.).

I think the trouble maybe coming from echo'ing out color commands with one echo then putting out the characters to reset the font elsewhere. I asked on the bash list and ended up doing this:

   # Make the prompt dark red when the previous command has succeeded, or
   # bright green when it has failed (in keeping with the slightly backwards
   # way exit codes work :).
   red=$(tput setaf 1)
   bright_green=$(tput bold; tput setaf 2)
   reset=$(tput sgr0)
   # Namespace'ed last user command exit status.  We need this I think because
   # the tput commands in the subshells end up resetting $?.
   PROMPT_COMMAND='MYPROMPT_LUCES=$?'   
   colors=("$red" "$bright_green")
   PS1='\[${colors[$? != 0]}\]$(if [ $MYPROMPT_LUCES != 0 ]; then \
                                    echo "$MYPROMPT_LUCES "; \
                                fi)\$\[$reset\] '

which displays prompts following successful commands in dark red, and prompts following failing commands in bright green with the exit code shown.