freeCodeCamp/guide/english/bash/bash-cat/index.md

title
Bash Cat

Bash Cat

cat is one of the most frequently used commands in Unix operating systems.

cat is used to read a file sequentially and print it to the standard output. The name is derived from its function to concatenate files.

Cat can also be used to create a text file.

Usage

cat [options] [file_names]

Most used options:

• -b, number non-blank output lines
• -n, number all output lines
• -s, squeeze multiple adjacent blank lines
• -v, display non-printing characters, except for tabs and the end of line character

Example

Print in terminal the content of file.txt:

cat file.txt

Concatenate the content of the two files and display the result in terminal:

cat file1.txt file2.txt

Tip: Using cat on a directory will cause error, so make sure it's a readable file.

Creating a new text file:

cat > yourfile.txt

After pressing Enter, the cursor will be placed on the next line. You can start entering your desired text directly into your file. Press Ctrl+D or Ctrl+C to exit the file.

More Information:

• Wikipedia: https://en.wikipedia.org/wiki/Cat_(Unix)