getgui is a simple self-contained X11 GUI box that you can invoke from the command line, from within shell scripts, or from within C programs using an API.

Use it to get user responses, simple step-by-step "wizard" interfaces, or as a pop-up alarm clock to remind you when it's time to leave.

I've also found it useful for presenting an "In progress" message immediately when an app is launched from a desktop menu (especially for apps that take a while to visibly start up), to prevent naive users from repeatedly pressing the launch button.

Quick and easy!

Man pages:
  • Introduction
  • getgui(1) command line tool
  • getguilib(3) C API
  • hackster(1) X11 asteroids game that demonstrates getgui
  • Download page
  • Copyright
  • Other free software by Steve