tldr/pages/linux/nl.md

nl

A utility for numbering lines, either from a file, or from standard input.

• Number lines in a file:

nl {{file}}

• Number only the lines with printable text:

nl -t {{file}}

• Number only the body lines that match a basic regular expression (BRE) pattern:

nl -b p'FooBar[0-9]' {{file}}