Prompt Jobs

prompt-jobs.sh is Bourne-ish shell code to colorize your shell prompt, and add a list of currently suspended shell jobs.

It will take a prompt like:

my-prompt$

and transform it like:

my-prompt(1man|2ls)$

(where “man” and “ls” are suspended jobs in the current shell).

Demonstration video, courtesy of Asciinema:

The colors and list decorations are customizable. You can also disable the color mode, in which case it may look more like:

my-prompt(1:man 2:ls)$

There is a Mercurial source repository, which also includes an extensive suite of tests. If you just want the shell script, you can download it here; you are highly encouraged to also download the GPG signature, and verify the authenticity of the shell script before using it in your interactive shell.

To verify the signature, run gpg --keyserver keys.gnupg.net --recv-keys 297D9992, followed by gpg --verify prompt-jobs.sh.asc

To use the script, do not execute it; it must be sourced into your current shell environment:

. ./prompt-jobs.sh

(That’s “dot”, “space”, “dot slash prompt-jobs dot sh”.)

Once you’ve done that, your prompt should be immediately colored (if it wasn’t already). The shell script does its best to leave intact any special commands that were executed previously as part of your prompt.

Try starting a couple of shell jobs (such as man man or ls | less, and then suspending them with ^Z; you should see them show up in your prompt (resume them with fg %1, where 1 is the number of the jobs you wish to resume.

To automatically start your shell with these customizations, try putting the script in your home directory, as .prompt-jobs.sh (notice the leading dot, to hide it from normal directory listings), and then add something like the following to your ~/.profile, ~/.bashrc, ~/.kshrc, ~/.zshrc, or whatever’s appropriate for your environment:

    if [ -r ~/.prompt-jobs.sh ]; then
        . ~/.prompt-jobs.sh
    fi

The colors/graphical settings added to your prompt may be customized. Run the shell command set | egrep '^PJOBS_.*(TPUT|LIST|STR)=' to get a list of customizable shell variables you can set (before sourcing prompt-jobs.sh), that will change the graphical effects and text decorations used for various bits of the customized prompt. The TPUT bits are semicolon (;)-separated terminfo capability names (which you can find in terminfo(5); man 5 terminfo); the other bits are used to indicate what characters surround and separate list elements with.

You can place custom settings of these variables in a file called ~/.pjobsrc, and prompt-jobs.sh will source it automatically. To cause your changes to take effect, run the command pjobs-remove, and then re-source prompt-jobs.sh as you did before.

If you do not like color prompts, you can also set the variable PJOBS_HAVE_COLOR to anything other than y, and pjobs will choose the uncolored version of the prompt.

prompt-jobs.sh has been tested on bash, ksh (both the modern and ’88 versions), zsh, and dash. It does not work with Bourne-incompatible shells like csh or tcsh, and can not work on shells that don’t provide a means to execute commands as part of the prompt (usually via $(cmd) expansion; or the PROMPT_COMMAND shell variable on bash).

NOTE: prompt-jobs.sh puts many (invisible) characters into the prompt. Some shells, including bash and ksh, have been known to produce graphical glitches when moving around in shell history, or editing particularly large shell lines, if the prompt’s length (including the invisible characters) exceeds a certain length. If you experience these, consider simplifying the graphical effects you use in prompt-jobs.sh, or disabling the color support (as detailed above).

See the NOTES file for additional information.

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