Usage: nl [OPTION]... [FILE]...
Write each FILE to standard output, with line numbers added.
With no FILE, or when FILE is -, read standard input.

Mandatory arguments to long options are mandatory for short options too.
  -b, --body-numbering=STYLE      use STYLE for numbering body lines
  -d, --section-delimiter=CC      use CC for separating logical pages
  -f, --footer-numbering=STYLE    use STYLE for numbering footer lines
  -h, --header-numbering=STYLE    use STYLE for numbering header lines
  -i, --line-increment=NUMBER     line number increment at each line
  -l, --join-blank-lines=NUMBER   group of NUMBER empty lines counted as one
  -n, --number-format=FORMAT      insert line numbers according to FORMAT
  -p, --no-renumber               do not reset line numbers at logical pages
  -s, --number-separator=STRING   add STRING after (possible) line number
  -v, --starting-line-number=NUMBER  first line number on each logical page
  -w, --number-width=NUMBER       use NUMBER columns for line numbers
      --help     display this help and exit
      --version  output version information and exit

By default, selects -v1 -i1 -l1 -sTAB -w6 -nrn -hn -bt -fn.  CC are
two delimiter characters for separating logical pages, a missing
second character implies :.  Type \\ for \.  STYLE is one of:

  a         number all lines
  t         number only nonempty lines
  n         number no lines
  pBRE      number only lines that contain a match for the basic regular
            expression, BRE

FORMAT is one of:

  ln   left justified, no leading zeros
  rn   right justified, no leading zeros
  rz   right justified, leading zeros


Report nl bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
For complete documentation, run: info coreutils 'nl invocation'