Manual browser: editor(1)
editor — Text editor
editor is a text editor with a graphical user interface. It can be used as a filter as well: reading data from the standard input and writing it back to the standard output, together with any modification made.
The filename of a file to edit can be supplied directly on the command line. The following option is supported:
Enables filter mode.
Issues can be listed and reported at http://www.defora.org/os/project/bug_list/253/Editor.