Add numbers to the beginning of every line in a file

bash row-number
Village picture Village · Nov 21, 2011 · Viewed 43.7k times · Source

How can I add numbers to the beginning of every line in a file?

E.g.:

This is
the text
from the file.

Becomes:

000000001 This is
000000002 the text
000000003 from the file.

Answer

tamasgal picture tamasgal · Nov 21, 2011

Don't use cat or any other tool which is not designed to do that. Use the program:

nl - number lines of files

Example: 

nl --number-format=rz --number-width=9 foobar

Because nl is made for it ;-)

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