Bash & Linux·Bash from first command to automation

Pipes and redirection

Connect commands and send output where you want it.

Beginner 13 min read Lesson 4 of 300 Challenge included

What you will be able to do

Use | to chain commands.
Use > to overwrite and >> to append.
Use 2> for errors and 2>&1 to merge streams.
Use tee to write and display at once.

In plain English

A pipe sends stdout of one command to stdin of another. Redirection writes stdout to a file with > (overwrite) or >> (append), and 2> captures stderr. Small commands composed with pipes solve big problems.

terminalTerminal

ls -la | grep ".md" | wc -l
echo "build started" >> build.log
npm run build 2>&1 | tee build.log

Your turn

Count Markdown files

Easy

Count the .md files in the current directory using a pipe.

BASH · starter

ls

Check your understanding before moving on.

Knowledge checkQuestion 1

Which operator appends output to a file?

Select an answer to continue

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Next: Text processing

Lesson 4 of 300 · 0% of course