What is the purpose of "&&" in a shell command?

bash shell command-line syntax
Captain picture Captain · Dec 22, 2010 · Viewed 405.9k times · Source

As far as I know, using & after the command is for running it in the background.

Example of & usage: tar -czf file.tar.gz dirname &

But how about &&? (look at this example: https://serverfault.com/questions/215179/centos-100-disk-full-how-to-remove-log-files-history-etc#answer-215188)

Answer

girasquid picture girasquid · Dec 22, 2010

&& lets you do something based on whether the previous command completed successfully - that's why you tend to see it chained as do_something && do_something_else_that_depended_on_something.

Related questions

How do I set a variable to the output of a command in Bash?

I have a pretty simple script that is something like the following: #!/bin/bash VAR1="$1" MOREF='sudo run command against $VAR1 | grep name | cut -c7-' echo $MOREF When I run this script from the command line and pass it …

Read More
How to reload .bash_profile from the command line?

How can I reload .bash_profile from the command line? I can get the shell to recognize changes to .bash_profile by exiting and logging back in but I would like to be able to do it on demand.

Read More
find -mtime files older than 1 hour

I have this command that I run every 24 hours currently. find /var/www/html/audio -daystart -maxdepth 1 -mtime +1 -type f -name "*.mp3" -exec rm -f {} \; I would like to run it every 1 hour and delete files that are older than 1 …

Read More