alerta: show GUI dialogs from the command line

alerta is a small command-line tool that will display a simple graphical X11 dialog to the user.

It is similar to Zenity and KDialog, but statically linked and with zero C/C++ dependencies.

In addition to being a command-line tool, alerta can also be used as a Rust library, for showing simple dialogs from Rust applications that don't want to pull in an entire GUI framework.

Goals

• Produce a <1 MB statically linked executable.
• No hard dependencies on xcb, xlib, or other C libraries.
• Try not to look completely out of place in common desktop environments.

Showcase

$ alerta "Hello World!"

$ alerta --icon=error --title="Oh no!" --theme=dark --buttons=retrycancel $'Whoops!\n\nAn error has occurred!'

$ alerta --icon=question --title="Fries?" --theme=dark --buttons=yesno "Would you like some fries with that?"