What is the meaning of !#:3?

Question

 curl http://beyondgrep.com/ack-2.02-single-file > ~/bin/ack && chmod 0755 !#:3

What is the meaning of !#:3, from ack installation guide?

See also: http://stackoverflow.com/questions/12885417/unfamiliar-shell-syntax-in-ack-grep-install-script — Andy Lester, May 03 '13 at 21:08

jbr · Accepted Answer · 2013-04-23T09:41:25.477

16

In bash or zsh ! denotes a history command (not a shebang line which is #!, and has nothing to do with bash or zsh as such).

!# means the entire command line typed so far, and :3 selects the third word, in this case ~/bin/ack.

So the command is equivalent to:

 curl http://beyondgrep.com/ack-2.02-single-file > ~/bin/ack && chmod 0755 ~/bin/ack

edited Apr 23 '13 at 09:41

answered Apr 23 '13 at 08:59

jbr

1 Answers1