I'm writing some custom installers that will work on Ubuntu and I'm using the dialog
utility to help simplify the process of getting user input.
Sometimes, I notice that the extended ASCII that dialog outputs (such as line frames around text boxes) is not displayed correctly. (you get the circle with a question mark in it). This seems to happen when a system has been provisioned using the PXE/Netboot installer.
I'm wondering, given that the only language I need to support is English, what locale I should check for and suggest installing prior to launching dialog?
I've noticed this across multiple releases, my question isn't specific to a certain release.
Encoding is the only part of locale that should matter in this case, make sure that it's UTF-8.
Check that the font you use in a terminal contains the line-drawing characters.
Try
or
to get reliable results. At least the first one shouldn't need further installations.