I’m not really seeing the appeal of a program that (deep breath) makes most non-English text unreadable, and replaces perfectly cromulent characters like quotes, dashes, non-breaking spaces, currency symbols, mathematical symbols and emoji with a bunch of octal(!) junk.
It’s an interesting historical example of a utility that was useful in the days when Unix belonged to American guys with VT-52s, but no one should letting museum pieces like isgraph do their work for them nowadays.
I had to check the timestamp of the post to make sure it wasn’t written in 1995…
And since it doesn’t appear to treat a literal backslash in its input any differently from any other “normal” ASCII character, it also produces ambiguous output – something I’d very much have expected a tool like that to want to avoid.
I use vis sometimes when dealing with binary/corrupted files in my terminal text editor, which makes moving around hard when some characters aren’t visible.
A modern version of this utility that preserves unicode symbols would be handy.
This is also useful also to view spaces vs tabs or type of newlines.
Undisguised self advertising, I made 2 related programs: