Notice

This package is obsolete because there is a better alternative in Emacs 26 and later.

Emacs 26 officially provides the display-line-numbers function to show the line numbers and you can use the line-number-current-line face to highlight the current line number. They show the better performance than linum-mode and hlinum-mode.

hlinum-mode

This library extends linum-mode to highlight current line number. It requires Emacs 24.4 or later.

To use this package, add these lines to your .emacs file:

    (require 'hlinum)
    (hlinum-activate)

And by using M-x linum-mode, you can see line numbers with highlighting current line number.

You can customize the color of highlighting current line by changing linum-highlight-face. By default, hlinum highlights current line only in the active buffer. To highlight current line in all buffers, change linum-highlight-in-all-buffersp to t.