On: How to navigate directories faster with Bash (2015...

[RhysU]

I have an "mkcd" function in my startup files:

mkcd() { mkdir -vp "$1" && cd "$1"; }

[alsetmusic → RhysU]

Wait, now I'm confused. I have:

mkcd() { mkdir -p "$@" && cd "$_"; }

Can someone please detail the differences between $! and $_? (Apologies if I'm missing something obvious)

[tyingq → alsetmusic]

  $ echo "test" > /dev/null && echo !$
  /dev/null
  $ echo "test" > /dev/null && echo $_
  test

[karatinversion → alsetmusic]

You're thinking of $_ and !$, and I think they are equivalent - $_ is explicitly the last argument of the previous command, whereas !$ is a history expansion command. ! starts a new history expansion command, and $ is a word designator for the last word of the selected history entry. To quote man bash, " If a word designator is supplied without an event specification, the previous command is used as the event."

I would not that !$ is a bash-ism, whereas $_ works at least on zsh and ksh as well as bash.

[forgotmypw17 → RhysU]

     alias tcd='a=`date +%s`;mkdir "$a" && cd "$a"'

[gpspake → RhysU]

Yep, first thing I add to my dotfiles when I don't have it haha

[cutthegrass2 → RhysU]

+1, I do the same.

[bunsenhoneydew → cutthegrass2]

Me too