[vbird@www ~]$ LANG="en" 
# 还记得这个咚咚的用意吧？前面提过了，是为了『语系』的需要啊！下达过一次即可！ 
 
[vbird@www ~]$ man date 
DATE(1)                          User Commands                         DATE(1) 
# 请注意上面这个括号内的数字 
NAME  <==这个命令的完整全名，如下所示为date且说明简单用途为配置与显示日期/时间 
       date - print or set the system date and time 
 
SYNOPSIS  <==这个命令的基本语法如下所示 
       date [OPTION]... [+FORMAT] 
       date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]] 
 
DESCRIPTION  <==详细说明刚刚语法谈到的选项与参数的用法 
       Display  the  current  time  in  the given FORMAT, or set the system 
       date. 
 
       -d, --date=STRING  <==左边-d为短选项名称，右边--date为完整选项名称 
              display time described by STRING, not 'now' 
 
       -f, --file=DATEFILE 
              like --date once for each line of DATEFILE 
 
       -r, --reference=FILE 
              display the last modification time of FILE 
....(中间省略).... 
       # 找到了！底下就是格式化输出的详细数据！ 
       FORMAT controls the output.  The only valid option  for  the  second 
       form  specifies  Coordinated  Universal Time.  Interpreted sequences 
       are: 
 
       %%     a literal % 
 
       %a     locale's abbreviated weekday name (e.g., Sun) 
 
       %A     locale's full weekday name (e.g., Sunday) 
....(中间省略).... 
ENVIRONMENT  <==与这个命令相关的环境参数有如下的说明 
       TZ     Specifies the timezone, unless  overridden  by  command  line 
              parameters.   If  neither  is  specified,  the  setting  from 
              /etc/localtime is used. 
 
AUTHOR  <==这个命令的作者啦！ 
       Written by David MacKenzie. 
 
REPORTING BUGS  <==有问题请留言给底下的email的意思！ 
       Report bugs to <bug-coreutils@gnu.org>. 
 
COPYRIGHT  <==受到著作权法的保护！用的就是 GPL 了！ 
       Copyright ? 2006 Free Software Foundation, Inc. 
       This is free software.  You may redistribute copies of it under  the 
       terms      of      the      GNU      General      Public     License 
       <http://www.gnu.org/licenses/gpl.html>.  There is  NO  WARRANTY,  to 
       the extent permitted by law. 
 
SEE ALSO  <==这个重要，你还可以从哪里查到与date相关的说明文件之意 
       The  full  documentation for date is maintained as a Texinfo manual. 
       If the info and date programs are properly installed at  your  site, 
       the command 
 
              info date 
 
       should give you access to the complete manual. 
 
date 5.97                          May 2006                            DATE(1) 

DATE(1)                          User Commands                         DATE(1) 
 
NAME 
       date - print or set the system date and time 
 
SYNOPSIS 
       date [OPTION]... [+FORMAT] 
       date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]] 
 
DESCRIPTION 
       Display  the  current  time  in  the given FORMAT, or set the system date. 
 
....(中间省略).... 
 
/date <==只要按下/，光标就会跑到这个地方来，你就可以开始输入搜寻字符串咯 

[vbird@www ~]$ whatis  [命令或者是数据]   <==相当于 man -f [命令或者是数据] 
[vbird@www ~]$ apropos [命令或者是数据]   <==相当于 man -k [命令或者是数据] 

[root@www ~]# makewhatis