scmuser created the topic: Whats the difference between running a shell scrip
Whats the difference between running a shell script as ./script.sh and sh script.sh

have a script that looks like this

#!/bin/bash

function something() {
echo “hello world!!”
}

something | tee logfile

I have set the execute permission on this file and when I try running the file like this

$./script.sh

it runs perfectly fine, but when I run it on the command line like this

$sh script.sh

It throws up an error. Why does this happen and what are the ways in which I can fix this.

scmuser replied the topic: Re:Whats the difference between running a shell scrip
Running it as ./script.sh will make the kernel read the first line (the shebang), and then invoke bash to interpret the script. Running it as sh script.sh uses whatever shell your system defaults sh to (on Ubuntu this is Dash, which is sh-compatible, but doesn’t support some of the extra features of Bash).

You can fix it by invoking it as bash script.sh, or if it’s your machine you can change /bin/sh to be bash and not whatever it is currently (usually just by symlinking it – rm /bin/sh && ln -s /bin/bash /bin/sh). Or you can just use ./script.sh instead if that’s already working 😉

Rajesh Kumar

I’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday Landmark, stock market tips at Stocks Mantra, health and fitness guidance at My Medic Plus, product reviews at TrueReviewNow , and SEO strategies at Wizbrand.

Do you want to learn Quantum Computing?

Please find my social handles as below;

Rajesh Kumar Personal Website
Rajesh Kumar at YOUTUBE
Rajesh Kumar at INSTAGRAM
Rajesh Kumar at X
Rajesh Kumar at FACEBOOK
Rajesh Kumar at LINKEDIN
Rajesh Kumar at WIZBRAND