Shell steps (sh, bat) in Jenkins - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this Jenkins shell step?

Consider this Jenkins pipeline shell step using sh to list files. What will be the output if the workspace contains files file1.txt and file2.txt?

Jenkins

sh 'ls *.txt'

A file1.txt file2.txt

B No output, command fails

C ls: cannot access '*.txt': No such file or directory

D

file1.txt
file2.txt

💡 Hint

Think about how the shell expands wildcards and how Jenkins captures output.

The sh step runs the shell command and outputs matching files each on a new line.

❓ Troubleshoot

intermediate

Why does this Jenkins bat step fail on Windows agent?

This Jenkins pipeline step runs a Windows batch command but fails with 'command not found'. What is the likely cause?

Jenkins

bat 'echo Hello World'

A The <code>echo</code> command is misspelled

B The agent is Linux, so <code>bat</code> commands won't run

C The Jenkinsfile syntax is incorrect for <code>bat</code>

D The workspace path is invalid

💡 Hint

Consider the environment where the command runs.

The bat step runs Windows batch commands and requires a Windows agent. On Linux agents, it fails.

❓ Configuration

advanced

How to capture output of a shell step in Jenkins pipeline?

You want to save the output of a shell command into a variable in a Jenkins pipeline scripted syntax. Which snippet correctly captures the output?

A def result = sh(script: 'date')

B def result = bat(script: 'date', returnStdout: true)

C def result = sh(script: 'date', returnStdout: true).trim()

D def result = sh('date')

💡 Hint

Look for the option that returns command output as a string.

The sh step with returnStdout: true returns the command output as a string.

✅ Best Practice

advanced

Which approach is best for cross-platform shell steps in Jenkins pipeline?

You want to write a Jenkins pipeline that runs shell commands on both Linux and Windows agents. Which approach is best?

A Use <code>sh</code> step for Linux and <code>bat</code> step for Windows inside <code>if</code> condition checking OS

B Use only <code>sh</code> step for all agents

C Use only <code>bat</code> step for all agents

D Write commands in Groovy without shell steps

💡 Hint

Think about agent OS compatibility.

Using sh for Linux and bat for Windows with OS checks ensures commands run correctly on each platform.

🔀 Workflow

expert

Order the steps to run a shell command, capture output, and archive a file in Jenkins pipeline

Arrange these Jenkins pipeline steps in the correct order to run a shell command, save its output, and archive a file named output.log:

A 1,3,2,4

B 3,1,2,4

C 1,2,3,4

D 2,1,3,4

💡 Hint

Think about creating the file before reading and archiving it.

First create the file with shell command (1), then read it (3), archive it (2), and finally print confirmation (4).