nl [-p][-b type][-d delim][-f type][-h
type][-i incr][-l num][-n format]
[-s sep][-v startnum][-w width][file]
The nl utility shall read lines from the named file or the standard input if no file is named and shall reproduce the lines to standard output. Lines shall be numbered on the left. Additional functionality may be provided in accordance with the command options in effect.
The nl utility views the text it reads in terms of logical pages. Line numbering shall be reset at the start of each logical page. A logical page consists of a header, a body, and a footer section. Empty sections are valid. Different line numbering options are independently available for header, body, and footer (for example, no numbering of header and footer lines while numbering blank lines only in the body).
The starts of logical page sections shall be signaled by input lines containing nothing but the following delimiter characters:
Unless otherwise specified, nl shall assume the text being read |
is in a single logical page body. |
The nl utility shall conform to the Base Definitions volume |
of IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines. |