How to view the contents of a file using cat, less, or more?
Jun 14, 2025 am 12:21 AM
When viewing file content in Linux or Unix terminals, cat is suitable for quick viewing of small files, less is suitable for scrolling through large files, and more is used for page-by-page viewing but only supports page-forward turn. Specifically: 1. Use the cat command to quickly display the content of small files, support merge and pipeline operations, but cannot be paging; 2. Use the less command to scroll up and down, search and exit, suitable for viewing large logs or configuration files; 3. Use the more command to view content page by page but do not support rollback, suitable for resource-constrained environments or simple browsing. In practice, cat is used for small files, less is used for complex scenarios, and less is used for more.
If you're working in a Linux or Unix-like terminal and want to quickly check the contents of a file, cat , less , and more are three basic but powerful tools for the job. Each has its own strengths depending on what you're trying to do.
Use cat for quick viewing of small files
The cat command is short for "concatenate," and it's great for displaying the full content of a small file all at once. Just type:
cat filename.txt
This works best when the file isn't too long — otherwise, the text will fly by too fast to read. One useful trick is combining it with other commands via pipes, like cat filename | grep "search term" to filter content.
Some things to keep in mind:
- If the file has many lines, it scrolls past instantly — no chance to pause.
- It's often used in scripts or automation because it doesn't require user interaction.
- You can also use it to combine multiple files:
cat file1.txt file2.txt > combined.txt.
Scroll through large files with less
When dealing with bigger files, less is your go-to tool. It lets you scroll up and down, search, and exit gracefully. Run it like this:
less filename.log
Once inside:
- Press Enter to scroll line by line.
- Press Spacebar to jump a full page.
- Type
/followed by a search term to find something specific. - Press q to quit.
It's especially handy when looking through logs or config files that span hundreds or thousands of lines. And unlike more , which we'll cover next, less support backward scrolling too.
View one screen at a time with more
The more command is an older alternative to less . It's similar in that it shows you content page by page, but it only lets you move forward — no going back once you've scrolled past a section.
To use it:
more filename.txt
After each page:
- Press Spacebar to see the next page.
- Press Enter for one line at a time.
- Type
qto quit early.
It's not as flexible as less , but it's still useful in environments where fewer resources are available or if you just need to skim from top to bottom without jumping around.
In practice, most people stick with cat for small stuff and less for anything longer or more complex. more is still around but rarely preferred these days.
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