0371-0372.html

来自「linux-unix130.linux.and.unix.ebooks130 l」· HTML 代码 · 共 190 行

HTML

190 行





<HTML>

<HEAD>

<TITLE>Developer.com - Online Reference Library - 0672311739:RED HAT LINUX 2ND EDITION:GNU Project Utilities</TITLE>

<META NAME="ROBOTS" CONTENT="NOINDEX, NOFOLLOW">
<SCRIPT>
<!--
function displayWindow(url, width, height) {
        var Win = window.open(url,"displayWindow",'width=' + width +
',height=' + height + ',resizable=1,scrollbars=yes');
}
//-->
</SCRIPT>
</HEAD>

 -->




<!-- ISBN=0672311739 //-->

<!-- TITLE=RED HAT LINUX 2ND EDITION //-->

<!-- AUTHOR=DAVID PITTS ET AL //-->

<!-- PUBLISHER=MACMILLAN //-->

<!-- IMPRINT=SAMS PUBLISHING //-->

<!-- PUBLICATION DATE=1998 //-->

<!-- CHAPTER=17 //-->

<!-- PAGES=0351-0372 //-->

<!-- UNASSIGNED1 //-->

<!-- UNASSIGNED2 //-->









<P><CENTER>

<a href="0368-0370.html">Previous</A> | <a href="../ewtoc.html">Table of Contents</A> | <a href="../ch18/0373-0376.html">Next</A>

</CENTER></P>



<A NAME="PAGENUM-371"><P>Page 371</P></A>





<TABLE WIDTH="360">

<TR><TD>

blank

</TD><TD>

Horizontal whitespace

</TD></TR>

<TR><TD>

cntrl

</TD><TD>

Control characters

</TD></TR>

<TR><TD>

digit

</TD><TD>

Digits

</TD></TR>

<TR><TD>

graph

</TD><TD>

Printable characters, not including space

</TD></TR>

<TR><TD>

lower

</TD><TD>

Lowercase letters

</TD></TR>

<TR><TD>

print

</TD><TD>

Printable characters, including space

</TD></TR>

<TR><TD>

punct

</TD><TD>

Punctuation characters

</TD></TR>

<TR><TD>

space

</TD><TD>

Horizontal or vertical whitespace

</TD></TR>

<TR><TD>

upper

</TD><TD>

Uppercase letters

</TD></TR>

<TR><TD>

xdigit

</TD><TD>

Hexadecimal digits

</TD></TR>

</TABLE>















<P>The way to invoke tr with one of these character classes is

`[:classname:]'. To get rid of punctuation, use the

punct class:

</P>





<!-- CODE SNIP //-->

<PRE>

tr `[:punct:]' ` ` &lt; ~/docs/ch16.doc |

tr `A-Z' `a-z' | tr -s ` ` | tr -d `\t\n' |

tr ` ` `\n' | sort | uniq -c | sort -rn

</PRE>

<!-- END CODE SNIP //-->











<P>Here's some of the new output:

</P>





<!-- CODE //-->

<PRE>



405 the

170 to

136 a

134 of

122 and

119 is

 80 files

 74 file

 72 in

 67 or

</PRE>

<!-- END CODE //-->











<P>The numbers are different for some of the words because I have been running the

commands and writing the chapter at the same time.

</P>









<P>I could also have replaced `A-Z' and `a-z' with the

upper and lower classes, but there is no real advantage to using the classes, and the ranges

are much more illustrative of the process.

</P>









<H3><A NAME="ch17_ 20">

Summary

</A></H3>









<P>This chapter covers the four major GNU utilities packages and the major commands in

each of these packages. As you have seen in the various examples, the real power of these

packages lies in their capability to help the user break down complex tasks and solve them quickly.

</P>



<A NAME="PAGENUM-372"><P>Page 372</P></A>













<P><CENTER>

<a href="0368-0370.html">Previous</A> | <a href="../ewtoc.html">Table of Contents</A> | <a href="../ch18/0373-0376.html">Next</A>

</CENTER></P>









</td>
</tr>
</table>

<!-- begin footer information -->





</body></html>

0371-0372.html - 源码说明

本页面展示了「linux-unix130.linux.and.unix.ebooks130 linux and unix ebookslinuxLearning Linux - Collection of 12 E」中的 0371-0372.html 源码文件，采用 HTML 编程语言编写，共 190 行代码。您可以在线阅读完整代码内容，也可以返回资源详情页下载完整源码包进行本地学习和开发。

虫虫开发者社区收录了大量与linux相关的技术资源，包括源代码、技术文档、电路图等，是电子工程师和嵌入式开发者的专业学习平台。

⌨️ 快捷键说明

复制代码Ctrl + C

搜索代码Ctrl + F

全屏模式F11

增大字号Ctrl + =

减小字号Ctrl + -

显示快捷键?