You can even put ANSI escape sequences in file names, since there is no notion of an encoding for file names in POSIX. They're just strings of any byte except /

You can even put ANSI escape sequences in file names, since there is no notion of an encoding for file names in POSIX. They're just strings of any byte except / and NUL. Fortunately GNU ls won't print most escape sequences verbatim to stdout, but other implementations and/or programs might, and I have had some success creating a file name that GNU ls always prints in a fixed color (this was a while ago, don't have it on hand).