19 Nov 2009

Tip: ^ and ! in the shell « Richard WM Jones

So don’t people know about using ^ and ! in the shell?!? Last week I watched an experienced Linux user carefully hit the ↑ cursor key to get a previous line of history, then ←&→ just to make a simple edit!

Here’s my 30 second guide:

!! Repeat the previous command. Example: 
$ ls
bin  d  Desktop  rpmbuild  tmp
$ !!
ls
bin  d  Desktop  rpmbuild  tmp
!-2 (etc) Repeat the command 2 previously (so !! = !-1), or for any number previously. This is the most useful I think.
^foo^bar Replace foo with bar in the previous command. eg: 
$ ls -l /etx/httpd/conf.d/local.conf
ls: cannot access /etx/httpd/conf.d/local.conf: No
such file or directory
$ ^etx^etc
ls -l /etc/httpd/conf.d/local.conf
-rw-r--r-- 1 root root 76 2009-07-16 14:59 /etc/httpd/conf.d/local.conf
!foo Run the most recent command that started foo, eg: 
$ !ls
ls -l /etc/httpd/conf.d/local.conf
-rw-r--r-- 1 root root 76 2009-07-16 14:59 /etc/httpd/conf.d/local.conf

Today I discovered that these are called event designators.

via rwmj.wordpress.com

Nice