Append to a file text, a blank line, and the last line of another file 

echo -e "From: me\n\n$(tail -n1 /var/log/apache2/error.log)" >> file

June 21, 2012 — kevin

Explanation

  • -e option to echo makes it interpret '\n' as a newline
  • $(command) syntax runs a command, then uses its output in place

Limitations

The -e flag of echo doesn't work on all systems. In that case you can use printf instead.

text-processing file-manipulation
tail echo file

Alternative one-liners

Append to a file text, a blank line, and the last line of another file 

{ echo some text; echo; tail -n1 /var/log/apache2/error.log; } >> /path/to/file

June 22, 2012 — bashoneliners