What is your single most favorite command-line trick using Bash? [closed]

Answer 1

ESC.

Inserts the last arguments from your last bash command. It comes in handy more than you think.

cp file /to/some/long/path

cd ESC.

Answer 2

rename

Example:

$ ls
this_has_text_to_find_1.txt
this_has_text_to_find_2.txt
this_has_text_to_find_3.txt
this_has_text_to_find_4.txt

$ rename 's/text_to_find/been_renamed/' *.txt
$ ls
this_has_been_renamed_1.txt
this_has_been_renamed_2.txt
this_has_been_renamed_3.txt
this_has_been_renamed_4.txt

So useful

Answer 3

When downloading a large file I quite often do:

while ls -la <filename>; do sleep 5; done

And then just ctrl+c when I'm done (or if ls returns non-zero). It's similar to the watch program but it uses the shell instead, so it works on platforms without watch.

Another useful tool is netcat, or nc. If you do:

nc -l -p 9100 > printjob.prn

Then you can set up a printer on another computer but instead use the IP address of the computer running netcat. When the print job is sent, it is received by the computer running netcat and dumped into printjob.prn.

Answer 4

Using 'set -o vi' from the command line, or better, in .bashrc, puts you in vi editing mode on the command line. You start in 'insert' mode so you can type and backspace as normal, but if you make a 'large' mistake you can hit the esc key and then use 'b' and 'f' to move around as you do in vi. cw to change a word. Particularly useful after you've brought up a history command that you want to change.

Answer 5

type -a PROG

in order to find all the places where PROG is available, usually somewhere in ~/bin rather than the one in /usr/bin/PROG that might have been expected.

Answer 6

I often have aliases for vi, ls, etc. but sometimes you want to escape the alias. Just add a back slash to the command in front:

Eg:

$ alias vi=vim
$ # To escape the alias for vi:
$ \vi # This doesn't open VIM

Cool, isn't it?