📄 0066-0068.html

📁 linux-unix130.linux.and.unix.ebooks130 linux and unix ebookslinuxLearning Linux - Collection of 12 E
💻 HTML
字号:




<HTML>

<HEAD>

<TITLE>Sams Teach Yourself Linux in 24 Hours:Manipulation and Searching Commands:EarthWeb Inc.-</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=0672311623 //-->

<!-- TITLE=Sams Teach Yourself Linux in 24 Hours//-->

<!-- AUTHOR=Bill Ball//-->

<!-- PUBLISHER=Macmillan Computer Publishing//-->

<!-- IMPRINT=Sams//-->

<!-- CHAPTER=05 //-->

<!-- PAGES=0063-0082 //-->

<!-- UNASSIGNED1 //-->

<!-- UNASSIGNED2 //-->







<P><CENTER>

<a href="0063-0065.html">Previous</A> | <a href="../ewtoc.html">Table of Contents</A> | <a href="0069-0071.html">Next</A>

</CENTER></P>



<A NAME="PAGENUM-66"><P>Page 66</P></A>





<P>

directory. This is a safe, but not fail-safe, approach to deleting or recovering files. You

may also be able to use the mc command, or Midnight Commander, discussed later in

this chapter.

</P>



<H4><A NAME="ch05_ 7">

Creating Directories with the mkdir Command

</A></H4>



<P>The mkdir command can create one or several directories with a single command line.

You may also be surprised to know that mkdir can also create a whole hierarchy of

directories, which includes parent and children, with a single command line.

</P>



<P>This command is one of the basic tools (along with

cp and mv) you'll use to organize your information. Now, take a look at some examples. The following simple command

line creates a single directory:

</P>



<!-- CODE SNIP //-->

<PRE>

# mkdir temp

</PRE>

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



<P>But you can also create multiple directories with

</P>



<!-- CODE SNIP //-->

<PRE>

# mkdir temp2 temp3 temp4

</PRE>

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



<P>You'd think that you could also type the following to make a directory named

child under temp:

</P>



<!-- CODE SNIP //-->

<PRE>

# mkdir temp/child

</PRE>

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



<P>And you can, because the temp directory exists (you just created it). But,

suppose you type

</P>



<!-- CODE SNIP //-->

<PRE>

# mkdir temp5/child

mkdir: cannot make directory `temp5/child': No such file or directory

</PRE>

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



<P>As you can see, mkdir complained because the

temp5 directory did not exist. To build a hierarchy of directories with

mkdir, you must use the -p, or parent option, for example:

</P>



<!-- CODE //-->

<PRE>

# mkdir -p temp5/parent/child

# tree temp5

temp5

`-- parent

    `-- child



2 directories, 0 files

</PRE>

<!-- END CODE //-->



<P>As you can see, mkdir created not only the

temp5 directory, but also a subdirectory called

parent, and a subdirectory under parent called

child.

</P>



<P>Now that you know how to create directories, take a look at how to remove them.

</P>



<H4><A NAME="ch05_ 8">

Removing Directories with the rmdir Command

</A></H4>



<A NAME="PAGENUM-67"><P>Page 67</P></A>









<P>The rmdir command is used to remove directories. To remove a directory, all you have

to do is type

</P>



<!-- CODE SNIP //-->

<PRE>

# rmdir tempdirectory

</PRE>

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



<P>But there's a catch: the directory must be empty first! If you try to delete a directory

with any files, you'll get an error message like this:

</P>



<!-- CODE SNIP //-->

<PRE>

# rmdir temp5

rmdir: temp5: Directory not empty

</PRE>

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



<P>In this example, temp5 also contains other directories. The

rmdir command would also complain if a directory contains only files and not directories. You can use the

rm command to remove the files first (remember to be careful if you use the

-fr option), or you can move the files somewhere else, or rename the directory, with the

mv command, discussed next.

</P>



<P>The rmdir command, like mkdir, also has a -p, or parent, option. You can use this

option to remove directory hierarchies, for example:

</P>



<!-- CODE SNIP //-->

<PRE>

# rmdir -p temp5

rmdir: temp5: Directory not empty

</PRE>

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



<P>Hmm. That didn't work! How about

</P>



<!-- CODE SNIP //-->

<PRE>

# rmdir -p temp5/parent

rmdir: temp5/parent: Directory not empty

</PRE>

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



<P>Hey! That didn't work either. Now try

</P>



<!-- CODE SNIP //-->

<PRE>

# rmdir -p temp5/*

rmdir: temp5/parent: Directory not empty

</PRE>

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



<P>This is getting frustrating! Try it one more time:

</P>



<!-- CODE SNIP //-->

<PRE>

# rmdir -p temp5/parent/child

</PRE>

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



<P>Finally! As you can see, you must specify the complete directory tree to delete it. If

you use the same command line, but without the -p option, only the child directory would

be deleted. But what if there are two or more subdirectories, for example:

</P>



<!-- CODE //-->

<PRE>

# mkdir -p temp5/parent/child

# mkdir temp5/parent/child2

# tree temp5

temp5

`-- parent

    |-- child

    `-- child2



3 directories, 0 files

</PRE>

<!-- END CODE //-->



<P>In order to delete the entire directory system of

temp5, you'd need to use

</P>



<A NAME="PAGENUM-68"><P>Page 68</P></A>







<!-- CODE SNIP //-->

<PRE>

# rmdir temp5/parent/*

</PRE>

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



<P>So far, you've seen how to create and remove directories. Next, you'll learn about the

mv command, which you can use to move or rename files and directories.

</P>



<H4><A NAME="ch05_ 9">

Renaming Files with the mv Command

</A></H4>



<P>The mv command, called a rename command but known to many as a move

command, will indeed rename files or directories, but it will also move them around your file system.

</P>



<P>Actually, in the technical sense, the files or directories are not really moved. If you

insist on knowing all the gory details, read the Linux System Administrator's

Guide, available through

</P>



<!-- CODE SNIP //-->

<PRE>

<a href="http://sunsite.unc.edu/ldp/ldp/sag/index.html">

http://sunsite.unc.edu/LDP/LDP/sag/index.html</A>

</PRE>

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



<P>In its simplest form, mv can rename files, for example:

</P>



<!-- CODE SNIP //-->

<PRE>

# touch file1

# mv file1 file2

</PRE>

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



<P>This command renames file1 to file2. However, besides renaming files,

mv can rename directories, whether empty or not, for example:

</P>



<!-- CODE SNIP //-->

<PRE>

# mkdir -p temp/temp2/temp3

# mv temp newtemp

</PRE>

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



<P>Although mv has nine different options, this section concentrates on

the two most commonly used. These options, -b and

-i, allow you to use mv in a fairly safe way,

because mv will not only rename, but overwrite silently and quickly! The first option,

-b, creates a backup of any file or directory you rename to an existing name, for example:

</P>



<!-- CODE SNIP //-->

<PRE>

# touch file1 file2 file3

# ls file*

file1  file2  file3

# mv file1 file2

# ls file*

file1 file2

</PRE>

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



<P>As you can see, without using -b, mv not only renamed

file1 to file2, but deleted file2 in the process. Is this dangerous? You bet! Now, try the

-b option:

</P>



<!-- CODE SNIP //-->

<PRE>

# touch file1

# ls file*

file1 file2 file3

# mv -b file1 file2

# ls file*

file2   file2~  file3

</PRE>

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



<P>This example shows that although file1 has been renamed, replacing

file2, a backup of file2 with a default extension of the tilde

(~) has been created.

</P>



<P><CENTER>

<a href="0063-0065.html">Previous</A> | <a href="../ewtoc.html">Table of Contents</A> | <a href="0069-0071.html">Next</A>

</CENTER></P>











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

<!-- begin footer information -->









</body></html>
⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -