In shell scripts you can use $1 to refer to the first argument, $2 for the second, etc. If you want to refer to all arguments (e.g. when writing a bash script that takes an arbitrary amount of arguments and passes them on to another call), you may not want to do a “$1 $2 $3 $4 ...”.

Use $@ instead, like in this script:
$ cat welcome
#!/bin/bash
echo Hello to $@

When called, the above would produce this:
$ ./welcome the world and universe
Hello to the world and universe

Note that $@ works for both sh and bash.

Arne Hartherz

makandra.com

Say thanks

Last edit

Almost 12 years ago

License

Source code in this card is licensed under the MIT License.

Async control flow in JavaScript: Promises, Microtasks, async/await

Slides for Henning's talk on Sep 21st 2017.

Understanding sync vs. async control flow

Talking to synchronous (or "blocking") API

print('script start')
html = get('/foo')
print(html)
print('s...

Delivering Carrierwave attachments to authorized users only

Preparation

To attach files to your records, you will need a new database column representing the filename of the file. To do this, add a new migration (rails g migration <name>) with the following content:

class AddAttachmentToNotes...

Posted by Arne Hartherz to makandra dev (2011-07-01 13:28)

Linux: Refer to all arguments of a script call

Related cards:

Understanding sync vs. async control flow

Talking to synchronous (or "blocking") API

Summary

Introduction

Preparation