bash use second argument of previous command

Question

how I can use the second argument of previous command in a new command ?

example, with

$ mkdir test 

I make a directory, how I can use the name of directory for change to this ?

$ mkdir test && cd use_var

Answer 1

$_ is the last (right-most) argument of the previous command.

mkdir gash && cd "$_"

(I don't create files or directories called test, that's the name of a shell built-in and can cause confusions)

Answer 2

With history expansion, you can refer to arbitrary words in the current command line

mkdir dir1 && cd "!#:1"
# 0     1   2  3  4

!# refers to the line typed so far, and :1 refers to word number one (with mkdir starting at 0).

If you use this in a script (i.e., a non-interactive shell), you need to turn history expansion on with set -H and set -o history.

Answer 3

Pressing Esc + . places the last argument of previous command on the current place of cursor. Tested in bash shell and ksh shell.

Answer 4

I use functions for this. Type this in your shell:

mkcd() { mkdir "$1" ; cd "$1" ; }

Now you have a new command mkcd.

If you need this repeatedly, put the line into the file ~/.bash_aliases (if you use bash; other shells use different names).