I once typed something like:
echo "test mail message" > /usr/bin/qmail
instead of:
echo "test mail message" | /usr/bin/qmail
and went on holiday. Many lessons learned.
echo "test mail message" > /usr/bin/qmail
instead of:
echo "test mail message" | /usr/bin/qmail
and went on holiday. Many lessons learned.
What's 'qmail'?
> qmail is a mail transfer agent (MTA) that runs on Unix. It was written, starting December 1995, by Daniel J. Bernstein as a more secure replacement for the popular Sendmail program; qmail's source code is in the public domain.
Not "what is the application 'qmail'" (I'm quite aware, thanks). But "what is the token 'qmail'" evaluated to by the shell.
If you prefer: "which qmail".
There are numerous ways in which $PATH can change. Shared profiles and other users modifying root's init among them. Intent isn't necessarily malicious. It can still be unexpected.
Really fscking annoying: scripts that include inline binary data.