Don't needlessly copy command-line arguments into fixed-size buffers.
Previously the program crashed if an overlong pathname was provided on
the command line. Also, some systems (such as GNU Hurd) don't define
MAXPATHLEN at all.
After renaming to "tio" it makes sense to change the escape key
accordingly. Hence, the new escape key is ^t.
Meaning, in session, its now ctrl-t + q to quit.
Renamed to "tio" because it is shorter and this new name also more
precisely reflects what the program is - a simple TTY terminal I/O
application.
"tio" can be considered short for terminal I/O or TTY I/O or a
combination of the two, whichever you prefer.
Also, wanted to avoid naming conflicts with other projects.
