Linux Common commands (9) NL command

The NL command is used in a Linux system to calculate the line number of a file. NL can automatically add a line number to the output file content! The default result is a bit different from Cat-n, NL can make the line number more display design, including the number of digits and whether auto-completion 0 and so on.
1 command format:
NL [Options] ... [File] ...
2 Command parameters:
-B: Specifies the way the line number is specified, mainly in two ways:
-B A: Indicates that the line number (similar to cat-n) is also listed, whether or not it is a blank line;
-B T: If there is a blank line, the empty line does not list the row number (default);
-N: List the method of line number representation, there are three main kinds:
-N LN: The line number is displayed at the left of the screen;
-N RN: The line number is displayed on the very right of its own field and does not add 0;
-N RZ: line number in its own field to the right of the display, and add 0;
-W: The number of digits occupied by the line number field.
-P does not restart the calculation at the logical delimiter.
3 Command function:
The NL command reads the File parameter (standard input by default), computes the line number in the input, and writes the computed line number to standard output. In the output, the NL command calculates the left line based on the flags that you specify on the command line. The input text must be written in a logical page. Each logical page has a header, a body, and a footer section (which can have an empty section). Unless you use the-P flag, the NL command re-sets the line number where each logical page begins. Row calculation flags can be set separately for header, body, and footer sections (for example, header and footer lines can be computed but text lines cannot)
4 usage Examples
List the contents of Log2012.log with NL
NL Log2012.log
The contents of Log2012.log are listed in NL, and the line numbers are added to the blank lines.
Nl-b a Log2012.log
Let the line number in front of the automatic 0, unified output format
Nl-b a-n RZ Log2014.log
Nl-b a-n rz-w 3 Log2014.log
Nl-b a-n RZ command line number default to six bits, to adjust the number of bits can be added to the parameter-W 3 is adjusted to 3 bits

Linux Common commands (9) NL command