This browser is no longer supported.

Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.

[email protected] - Bash v3 task

Use this task to run a Bash script on macOS, Linux, or Windows.

targetType - Type string . Allowed values: filePath (File Path), inline . Default value: filePath .

Targets script type: file path or inline.

filePath - Script Path string . Required when targetType = filePath .

The path of the script to execute. This must be a fully qualified path or relative to $(System.DefaultWorkingDirectory) .

arguments - Arguments string . Optional. Use when targetType = filePath .

The arguments passed to the shell script. Either ordinal parameters or named parameters.

script - Script string . Required when targetType = inline . Default value: # Write your commands here\n\necho 'Hello world' .

The contents of the script.

script - Script string . Required when targetType = inline . Default value: # Write your commands here\n\n# Use the environment variables input below to pass secret variables to this script .

script - Script string . Required when targetType = inline . Default value: # Write your commands here .

workingDirectory - Working Directory string .

Specifies the working directory in which you want to run the command. If you leave it empty, the working directory is $(Build.SourcesDirectory) .

failOnStderr - Fail on Standard Error boolean . Default value: false .

If this is true, this task will fail if any errors are written to the StandardError stream.

bashEnvValue - Set value for BASH_ENV environment variable string .

If the input is specified, its value is expanded and used as the path of a startup file to execute before running the script. If the environment variable BASH_ENV has already been defined, the task will override this variable only for the current task. Learn more about Bash Startup Files .

noProfile - Don't load the profile startup/initialization files boolean . Default value: true .

Don't load the system-wide startup file /etc/profile or any of the personal initialization files.

noRc - **Don't read the ~/.bashrc' initialization file**<br> boolean . Default value: true`.

Task control options

All tasks have control options in addition to their task inputs. For more information, see Control options and common task properties .

Output variables

The bash task has a shortcut in YAML: steps.bash .

The Bash task will find the first Bash implementation on your system. Running which bash on Linux/macOS or where bash on Windows will give you an idea of which one it will select.

Info about Bash startup files

The Bash task invokes the Bash as a non-interactive, non-login shell. When Bash is started non-interactively, to run a shell script, the Bash looks for the variable BASH_ENV in the environment, unfolds its value if it appears there, and uses the value as the name of a file to read and execute.

There are several options for defining the BASH_ENV environment variable in a pipeline. Firstly, it's possible to set the BASH_ENV environment variable as a pipeline variable. In this case, each instance of the Bash task will try to unfold the value of the BASH_ENV variable and use its value.

Another option is to set BASH_ENV for one particular instance of the Bash task, there are two ways how this can be done:

The first way is to use the bashEnvValue task input, see an example for reference:

Another way is to set the BASH_ENV variable as an environment variable for the pipeline task via the env keyword, for example:

Note that if the bashEnvValue input is defined in the Bash task, the pipeline task will override the value of the BASH_ENV variable with the value from the bashEnvValue input in a case when the BASH_ENV environment variable was already defined in the environment.

Bash scripts checked into the repo should be set executable ( chmod +x ). Otherwise, the task will show a warning and source the file instead.

You can map in variables using the env parameter which is common across all tasks , and is list of additional items to map into the process's environment. For example, secret variables are not automatically mapped. If you have a secret variable called Foo , you can map it in like this:

On macOS or Linux, the example above is equivalent to:

Requirements

Submit and view feedback for

Additional resources

Stack Exchange Network

Stack Exchange network consists of 181 Q&A communities including Stack Overflow , the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Super User is a question and answer site for computer enthusiasts and power users. It only takes a minute to sign up.

Q&A for work

Connect and share knowledge within a single location that is structured and easy to search.

Linux Bash Script, Single Command But Multiple Lines?

I have the following script I wrote by searching Google, and it backs up my Linux system to an archive:

This works, but I am wondering if I can format the script to show the command over multiple lines, something like this, so it is easy to edit later:

That way it is easier to read and edit later. Is it possible to format a Bash script this way?

Jay LaCroix's user avatar

5 Answers 5

All you should need to do is add "\" at the end of each line and it should be good to go.

So yours will look like:

A Few Shortcuts

(based on your comment update for setting $HOSTNAME)

Two options to set that:

Set HOSTNAME

HOSTNAME=$(hostname)

Use command substitution (e.g. $(command) )

So it would look like above. That just makes the command run before using it.

Another variable avoided would be easily:

$ man date will have the formats for the date options, the above is YYYYmmdd

Pablo A's user avatar

Use the backslash to continue a command on the next line:

Paul's user avatar

You can use this in bash

Community's user avatar

The same command, but with comments for each line, would be:

Alter Lagos's user avatar

Axel Heider provided a good alternative to backslashes. Two notes:

timkay's user avatar

Your Answer

Sign up or log in, post as a guest.

Required, but never shown

By clicking “Post Your Answer”, you agree to our terms of service , privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged linux bash script tar or ask your own question .

Hot Network Questions

task bash@3 multiline

Your privacy

By clicking “Accept all cookies”, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy .

Collectives™ on Stack Overflow

Find centralized, trusted content and collaborate around the technologies you use most.

Q&A for work

Connect and share knowledge within a single location that is structured and easy to search.

How to output a multiline string in Bash?

How can I output a multipline string in Bash without using multiple echo calls like so:

I'm looking for a portable way to do this, using only Bash builtins.

helpermethod's user avatar

11 Answers 11

Here documents are often used for this purpose.

They are supported in all Bourne-derived shells including all versions of Bash.

Dennis Williamson's user avatar

or you can do this:

Chris Mohr's user avatar

Inspired by the insightful answers on this page, I created a mixed approach, which I consider the simplest and more flexible one. What do you think?

First, I define the usage in a variable, which allows me to reuse it in different contexts. The format is very simple, almost WYSIWYG, without the need to add any control characters. This seems reasonably portable to me (I ran it on MacOS and Ubuntu)

Then I can simply use it as

or even better, when parsing parameters, I can just echo it there in a one-liner:

Jorge's user avatar

Use -e option, then you can print new line character with \n in the string.

For example:

Since I recommended printf in a comment, I should probably give some examples of its usage (although for printing a usage message, I'd be more likely to use Dennis' or Chris' answers). printf is a bit more complex to use than echo . Its first argument is a format string, in which escapes (like \n ) are always interpreted; it can also contain format directives starting with % , which control where and how any additional arguments are included in it. Here are two different approaches to using it for a usage message:

First, you could include the entire message in the format string:

Note that unlike echo , you must include the final newline explicitly. Also, if the message happens to contain any % characters, they would have to be written as %% . If you wanted to include the bugreport and homepage addresses, they can be added quite naturally:

Second, you could just use the format string to make it print each additional argument on a separate line:

With this option, adding the bugreport and homepage addresses is fairly obvious:

Gordon Davisson's user avatar

Also with indented source code you can use <<- (with a trailing dash) to ignore leading tabs (but not leading spaces).

For example this:

Outputs indented text without the leading whitespace:

Elliptical view's user avatar

I usually go with the builtin read command which I think is more flexible and intuitive. It reads the contents of a line into a variable, and allows for word splitting that is tied to the special shell variable IFS. Refer to this blog or even the man page for more details.

Zstack's user avatar

One more thing, using printf with predefined variable (here: msg ) as template.

This ^^^ will print whole message with additional vars inserted instead of %s in provided order.

i_want_more_edits's user avatar

assayag.org's user avatar

Output withOUT calling dedent first:

...and WITH calling dedent first (as shown above):

For a full explanation, see where I've already written about this:

And of course, thanks to @Andreas Louv for showing me the sed part of that function here .

Gabriel Staples's user avatar

Here is how I've done:

André Campos Rodovalho's user avatar

Your Answer

Sign up or log in, post as a guest.

Required, but never shown

By clicking “Post Your Answer”, you agree to our terms of service , privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged bash or ask your own question .

Hot Network Questions

task bash@3 multiline

Your privacy

By clicking “Accept all cookies”, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy .

Multi-Line String in Bash

Multi-Line String in Bash

This tutorial demonstrates different ways to print a multi-line string to a file in bash without putting extra space (indentation) by the use of here-document , shell variable, printf , echo , and echo with -e option.

Use here-document to Make Multi-Line String in Bash

From the output, we see that every set of words has its own line, and there are no extra spaces.

Use Shell Variable to Make Multi-Line String in Bash

Please enable JavaScript

Use printf to Make Multi-Line String in Bash

Use echo with the -e option to make multi-line string in bash, use echo to make multi-line string in bash.

Fumbani is a tech enthusiast. He enjoys writing on Linux and Python as well as contributing to open-source projects.

Related Article - Bash String

Stack Exchange Network

Stack Exchange network consists of 181 Q&A communities including Stack Overflow , the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. It only takes a minute to sign up.

Q&A for work

Connect and share knowledge within a single location that is structured and easy to search.

Here documents as multiple lines command within the bash

I created a snippet to test the here document

It come to Here document

It works properly, Unfortunately, it's not the case of structured command

I tried alternatively

What's the problem not allow the for command working?

AbstProcDo's user avatar

A here-document is a form of redirection. In your commands, you redirect into the cat command, and then try to use the output as a command in a command substitution.

The last example would expand to bash followed by a number of words. The first word is for , so bash would expect to run a shell script called for in the current directory, but fails in doing so.

In all examples, bash should also have complained that the here-document was not properly terminated (since the last line is EOF) with a trailing right parenthesis, not EOF ), saying something like

unless you are using an older bash release, like the default one on macOS.

Instead, this would be a better choice of actions as it avoids converting code into a string that needs to be re-interpreted and instead gives the document as a in-line shell script directly to a shell interpreter to execute.

The first of your examples work because it's a simple command.

Kusalananda's user avatar

Your Answer

Sign up or log in, post as a guest.

Required, but never shown

By clicking “Post Your Answer”, you agree to our terms of service , privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged bash or ask your own question .

Hot Network Questions

task bash@3 multiline

Your privacy

By clicking “Accept all cookies”, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy .

IMAGES

  1. A Bash Multiline Command| DiskInternals

    task bash@3 multiline

  2. A Bash Multiline Command| DiskInternals

    task bash@3 multiline

  3. List reset and multiline task import (with mobile)

    task bash@3 multiline

  4. A Bash Multiline Command| DiskInternals

    task bash@3 multiline

  5. A Bash Multiline Command| DiskInternals

    task bash@3 multiline

  6. Bash Scripting Multiline Comments

    task bash@3 multiline

VIDEO

  1. Big Bash League 2023

  2. Ben Swann Debates Gun Control On RT

  3. Bigg Boss 16

  4. 17-1 Improving Command-line Productivity bash basics

  5. umh4756 2013-14 Tema 1. Comandos básicos en GNU / Linux (parte 2): Redirección E/S, Tareas, Procesos

  6. Bigg Boss 16

COMMENTS

  1. [email protected]

    The first way is to use the bashEnvValue task input, see an example for reference: YAML steps: - task: [email protected] inputs: targetType: 'inline' script: env bashEnvValue: '~/.profile' Another way is to set the BASH_ENV variable as an environment variable for the pipeline task via the env keyword, for example: YAML

  2. Linux Bash Script, Single Command But Multiple Lines?

    Axel Heider provided a good alternative to backslashes. Two notes: The command can be included in the list, and; The use of the list should be in double quotes "${PARAMS[@]}", so that any spaces in parameters get preserved.

  3. How to output a multiline string in Bash?

    Here are two different approaches to using it for a usage message: First, you could include the entire message in the format string: printf "usage: up [--level <n>| -n <levels>] [--help] [--version] Report bugs to: up home page: ". Note that unlike echo, you must include the final newline explicitly.

  4. Multi-Line String in Bash

    Use Shell Variable to Make Multi-Line String in Bash Here, we are using a shell variable named greet. We have assigned a multi-line string to greet. greet="Hello > , > wolrd > !" The command below gets the multi-line string in the shell variable, greet, and redirects it to the specified file, multiline.txt, using >. echo "$greet" > multiline.txt

  5. shell

    2. I would like to process a multiline string and iterate it line by line, in a POSIX shell ( /bin/sh) on a BSD platform. Bash is not included in the base BSD-distribution and has a GPL license - so I am trying to make it universally work with /bin/sh instead. I found a solution using a pipe, however in the regular /bin/sh shell, these a ...

  6. Here documents as multiple lines command within the bash

    bash: warning: here-document at line 1 delimited by end-of-file (wanted `EOF') unless you are using an older bash release, like the default one on macOS. Instead, this would be a better choice of actions as it avoids converting code into a string that needs to be re-interpreted and instead gives the document as a in-line shell script directly ...