tweak - 3.02-6+b1 main

Tweak is a hex editor. It allows you to edit a file at very low
level, letting you see the full and exact binary contents of the
file. It can be useful for modifying binary files such as
executables, editing disk or CD images, debugging programs that
generate binary file formats incorrectly, and many other things.
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Tweak runs under any terminal emulator using the curses library. It
has customizable keybindings, but the default keybindings are similar
to emacs.