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Run multiple commands in one line with `;`, `&&` and `||` - Linux Tips

BC on January 15, 2020

There are 3 ways to run multiple shell commands in one line: 1) Use ; No matter the first command cmd1 run successfully or not, always ...
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Ian Pride • • Edited

Ternary (or more) operations on a single line:

[[ 1 -eq 1 ]] && echo true || echo false

[[ "${var}" == "string" ]] && ([[ "$(id -un)" == "root" ]] && echo ROOT || echo USER) || echo false
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And can be multiple lines:

[[ 1 -eq 1 ]] &&
echo true ||
echo false

[[ "${var}" == "string" ]] &&
([[ "$(id -un)" == "root" ]] &&
    echo ROOT ||
    echo USER) ||
echo false
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Thomas H Jones II •

I use the <CMD> && <SUCCESS_ACTION> || <FAIL_ACTION> method quite a lot ...annoying that BASH-linters complain about it.

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Chaitanya Shahare •

Thanks for these examples, they are really helpful

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BC •

Nice 👍 thanks for the add-up, Ian

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Ian Pride •

You're welcome; I just thought it would add a little perspective of how this concept can be used in various ways. Some might always prefer to use if/else statements to be safe & sometimes it is necessary, but I find myself using this type of 'shortcut' more times than not when it's safe to use.

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gokayburuc.dev •

I was searching that for a long time. Thanks a lot.

I added it to .bashrc and .zshrc files with the alias commands . And now one command is enough for the maintain system operations.

alias maintain_sys="sudo apt update &&
 sudo apt upgrade && 
sudo apt autoclean"
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Pankaj Sharma •

Thanks for that

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Bill Naylor • • Edited

I'm quite happy with using ';', '|', etc. however I generally am using them from an 'end-user' perspective. I frequently use commands like:

mvn clean package >& /tmp/out-comptest; less +G /tmp/out-comptest

then exit less, but may after want to see 'what was important in that file', is there a short hand way to run the last command of that sequence ... viz less +G /tmp/out-comptest?

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Nino •

Thanks

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Ajay Kumar •

thanks

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Michael Stangeland • • Edited

Can this be nested?

A && (B && echo passed || echo B failed ) || echo A failed

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nem8 •

Sure, but you need to re-write it slightly..
echo 'Test' > A
cat A && echo 'A passed' || echo 'A failed' && (cat B && echo 'B passed' || echo 'B failed')
Test
A passed
cat: B: No such file or directory
B failed