Built-in Variables in Awk

Power up your one-liners with built-in variables.

• NR: Number of Records (Line number)
• NF: Number of Fields (Columns in current row)
• FS: Field Separator

Example: Print lines longer than 80 characters (assuming space separated):

awk 'length($0) > 80' file.txt

Example: Print the last column of every row:

awk '{print $NF}' file.txt