Minicom fails unless it's run with root
privileges. As a normal user it fails to create
the lock file in /var/lock/LCK..modem.
The -o option does not override it. Is this a security
Minicom is shipped without the setgid bit needed to write in
/var/lock in order to minimize security risks. If you do
chgrp uucp /usr/bin/minicom
chmod g+s /usr/bin/minicom
then any user (not just root) will be able to create a lock file.