将文件nroff_file中的格式按下面的书写：

.TL
title of document
.AU
author name
.SH
section heading
.PP
paragraph ..
.PP
another paragraph ..
.SH
another section heading
.PP
etc.

用nroff来察看：
# nroff -ms  nroff_file | more
效果：

                     title of document

                        author name


section heading

     paragraph ..

     another paragraph ..

another section heading

     etc.