Do I have this command?

which <command> > /dev/null 2>&1 && echo Success!
or which <command> > /dev/null 2>&1 || echo Error! For example, I write which colordiff > /dev/null 2>&1 && alias diff=colordiff in my `~/.bashrc`.

By: skkzsh
2013-03-13 10:04:42

What Others Think

Perhaps more useful, is to use "type ". For example: which ls /bin/ls type ls ls is aliased to `ls -F --color=auto'
mpb · 490 weeks and 5 days ago
Thank you, but outputs of `which` and `type` on my environments are different from yours. For example: which ls ls: aliased to ls -Fh type ls ls is an alias for ls -Fh on Debian GNU/Linux 6.0 & Mac OS X 10.7.5. I always use `which` since its output is simple.
skkzsh · 490 weeks and 5 days ago
zsh: (( $+commands[colordiff] )) && echo "success" BTW, if you want both 'which' and 'type' you can provide which with the '--read-alias' switch, that is if your not using the builtin: % which which which='alias |/usr/bin/which --tty-only --read-alias --show-dot --show-tilde' /usr/bin/which
khayyam · 489 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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