coreutils: nl invocation
1
1 3.3 ‘nl’: Number lines and write files
1 ======================================
1
1 ‘nl’ writes each FILE (‘-’ means standard input), or standard input if
1 none are given, to standard output, with line numbers added to some or
1 all of the lines. Synopsis:
1
1 nl [OPTION]... [FILE]...
1
1 ‘nl’ decomposes its input into (logical) page sections; by default,
1 the line number is reset to 1 at each logical page section. ‘nl’ treats
1 all of the input files as a single document; it does not reset line
1 numbers or logical pages between files.
1
1 A logical page consists of three sections: header, body, and footer.
1 Any of the sections can be empty. Each can be numbered in a different
1 style from the others.
1
1 The beginnings of the sections of logical pages are indicated in the
1 input file by a line containing exactly one of these delimiter strings:
1
1 ‘\:\:\:’
1 start of header;
1 ‘\:\:’
1 start of body;
1 ‘\:’
1 start of footer.
1
1 The two characters from which these strings are made can be changed
1 from ‘\’ and ‘:’ via options (see below), but the pattern and length of
1 each string cannot be changed.
1
1 A section delimiter is replaced by an empty line on output. Any text
1 that comes before the first section delimiter string in the input file
1 is considered to be part of a body section, so ‘nl’ treats a file that
1 contains no section delimiters as a single body section.
1
11 The program accepts the following options. Also see ⇒Common
options.
1
1 ‘-b STYLE’
1 ‘--body-numbering=STYLE’
1 Select the numbering style for lines in the body section of each
1 logical page. When a line is not numbered, the current line number
1 is not incremented, but the line number separator character is
1 still prepended to the line. The styles are:
1
1 ‘a’
1 number all lines,
1 ‘t’
1 number only nonempty lines (default for body),
1 ‘n’
1 do not number lines (default for header and footer),
1 ‘pBRE’
1 number only lines that contain a match for the basic regular
11 expression BRE. ⇒Regular Expressions (grep)Regular
Expressions.
1
1 ‘-d CD’
1 ‘--section-delimiter=CD’
1 Set the section delimiter characters to CD; default is ‘\:’. If
1 only C is given, the second remains ‘:’. (Remember to protect ‘\’
1 or other metacharacters from shell expansion with quotes or extra
1 backslashes.)
1
1 ‘-f STYLE’
1 ‘--footer-numbering=STYLE’
1 Analogous to ‘--body-numbering’.
1
1 ‘-h STYLE’
1 ‘--header-numbering=STYLE’
1 Analogous to ‘--body-numbering’.
1
1 ‘-i NUMBER’
1 ‘--line-increment=NUMBER’
1 Increment line numbers by NUMBER (default 1).
1
1 ‘-l NUMBER’
1 ‘--join-blank-lines=NUMBER’
1 Consider NUMBER (default 1) consecutive empty lines to be one
1 logical line for numbering, and only number the last one. Where
1 fewer than NUMBER consecutive empty lines occur, do not number
1 them. An empty line is one that contains no characters, not even
1 spaces or tabs.
1
1 ‘-n FORMAT’
1 ‘--number-format=FORMAT’
1 Select the line numbering format (default is ‘rn’):
1
1 ‘ln’
1 left justified, no leading zeros;
1 ‘rn’
1 right justified, no leading zeros;
1 ‘rz’
1 right justified, leading zeros.
1
1 ‘-p’
1 ‘--no-renumber’
1 Do not reset the line number at the start of a logical page.
1
1 ‘-s STRING’
1 ‘--number-separator=STRING’
1 Separate the line number from the text line in the output with
1 STRING (default is the TAB character).
1
1 ‘-v NUMBER’
1 ‘--starting-line-number=NUMBER’
1 Set the initial line number on each logical page to NUMBER (default
1 1).
1
1 ‘-w NUMBER’
1 ‘--number-width=NUMBER’
1 Use NUMBER characters for line numbers (default 6).
1
1 An exit status of zero indicates success, and a nonzero value
1 indicates failure.
1