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</td>
<td class="docTableCell" vAlign="top">End-of-word anchor </td>
<td class="docTableCell" vAlign="top"><span class="docEmphasis">/love\>/</span>
</td>
<td class="docTableCell" vAlign="top">Matches lines containing a word that
ends with <span class="docEmphasis">love.</span> </td>
</tr>
<tr>
<td class="docTableCell" vAlign="top">
<p class="docText"><span class="docEmphasis">x\{m\}</span></p>
<p class="docText"><span class="docEmphasis">x\{m,\}</span></p>
<p class="docText"><span class="docEmphasis">x\{m,n\}</span><sup class="docFootnote"><a class="docLink" href="#ch04tabfn01">[a]</a></sup></td>
<td class="docTableCell" vAlign="top">
<p class="docText">Repetition of character x: m times</p>
<p class="docText">at least m times</p>
<p class="docText">at least m and not more than n times</td>
<td class="docTableCell" vAlign="top"><span class="docEmphasis">/o\{5\}/</span>
</td>
<td class="docTableCell" vAlign="top">Matches if line has 5 occurrences of
<span class="docEmphasis">o,</span> at least 5 occurrences of
<span class="docEmphasis">o,</span> or between 5 and 10 occurrences of
<span class="docEmphasis">o.</span></td>
</tr>
</table>
<blockquote>
<p class="docFootnote"><sup><a name="ch04tabfn01">[a]</a></sup> Not dependable
on all versions of UNIX or all pattern-matching utilities; usually works with
<span class="docEmphasis">vi</span> and <span class="docEmphasis">grep.</span></p>
</blockquote>
<h3 class="docSection1Title" id="ch04lev1sec6">4.6 <span class="docEmphasis">sed</span> Examples</h3>
<pre>% <span class="docEmphStrong">cat datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 43</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southwest SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">central CT Ann Stephens 5.7 .94 5 13</span>
</pre>
<h4 class="docSection2Title" id="ch04lev2sec2">4.6.1 Printing: The <span class="docEmphasis">p</span>
Command</h4>
<h5 id="ch04list04" class="docExampleTitle">Example 4.4 </h5>
<pre><span class="docEmphStrong">sed '/north/p' datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southwest SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">central CT Ann Stephens 5.7 .94 5 13</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">Prints all lines to standard output by default. If the
pattern <span class="docEmphasis">north</span> is found,
<span class="docEmphasis">sed</span> will print that line in addition to all
the other lines.</td>
</tr>
</table>
<h5 id="ch04list05" class="docExampleTitle">Example 4.5 </h5>
<pre><span class="docEmphStrong">sed -n '/north/p' datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">The <span class="docEmphasis">-n</span> option suppresses
the default behavior of <span class="docEmphasis">sed</span> when used with
the <span class="docEmphasis">p</span> command. Without the
<span class="docEmphasis">-n</span> option, <span class="docEmphasis">sed</span>
will print duplicate lines of output as shown in the preceding example. Only
the lines containing the pattern <span class="docEmphasis">north</span> are
printed when <span class="docEmphasis">-n</span> is used.</td>
</tr>
</table>
<pre>% <span class="docEmphStrong">cat datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southwest SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">central CT Ann Stephens 5.7 .94 5 13</span>
</pre>
<h4 class="docSection2Title" id="ch04lev2sec3">4.6.2 Deleting: The <span class="docEmphasis">d</span>
Command</h4>
<h5 id="ch04list06" class="docExampleTitle">Example 4.6 </h5>
<pre><span class="docEmphStrong">sed '3d' datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">central CT Ann Stephens 5.7 .94 5 13</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">Deletes the third line. All other lines are printed to
the screen by default.</td>
</tr>
</table>
<h5 id="ch04list07" class="docExampleTitle">Example 4.7 </h5>
<pre><span class="docEmphStrong">sed '3,$d' datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">The third line through the last line are deleted. The
remaining lines are printed. The dollar sign (<span class="docEmphasis">$</span>)
represents the last line of the file. The comma is called the
<span class="docEmphasis">range operato</span>r. In this example, the range
of addresses starts at line 3 and ends at the last line, which is
represented by the dollar sign (<span class="docEmphasis">$</span>).</td>
</tr>
</table>
<h5 id="ch04list08" class="docExampleTitle">Example 4.8 </h5>
<pre><span class="docEmphStrong">sed '$d' datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southwest SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">Deletes the last line. The dollar sign (<span class="docEmphasis">$</span>)
represents the last line. The default is to print all of the lines except
those affected by the <span class="docEmphasis">d</span> command.</td>
</tr>
</table>
<h5 id="ch04list09" class="docExampleTitle">Example 4.9 </h5>
<pre><span class="docEmphStrong">sed '/north/d' datafile</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southwest SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">central CT Ann Stevens 5.7 .94 5 13</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">All lines containing the pattern
<span class="docEmphasis">north</span> are deleted. The remaining lines are
printed.</td>
</tr>
</table>
<h4 class="docSection2Title" id="ch04lev2sec4">4.6.3 Substitution: The <span class="docEmphasis">s</span>
Command</h4>
<h5 id="ch04list10" class="docExampleTitle">Example 4.10 </h5>
<pre><span class="docEmphStrong">sed 's/west/north/g' datafile</span>
<span class="docEmphasis">northnorth NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">northern WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southnorth SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">central CT Ann Stephens 5.7 .94 5 13</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">The <span class="docEmphasis">s</span> command is for
substitution. The <span class="docEmphasis">g</span> flag at the end of the
command indicates that the substitution is global across the line; that is,
if multiple occurrences of <span class="docEmphasis">west</span> are found,
all of them will be replaced with <span class="docEmphasis">north.</span>
Without the <span class="docEmphasis">g</span> command, only the first
occurrence of <span class="docEmphasis">west</span> on each line would be
replaced with <span class="docEmphasis">north.</span></td>
</tr>
</table>
<pre>% <span class="docEmphStrong">cat datafile</span>
<span class="docEmphasis">northwest NW Charles Main 3.0 .98 3 34</span>
<span class="docEmphasis">western WE Sharon Gray 5.3 .97 5 23</span>
<span class="docEmphasis">southwest SW Lewis Dalsass 2.7 .8 2 18</span>
<span class="docEmphasis">southern SO Suan Chin 5.1 .95 4 15</span>
<span class="docEmphasis">southeast SE Patricia Hemenway 4.0 .7 4 17</span>
<span class="docEmphasis">eastern EA TB Savage 4.4 .84 5 20</span>
<span class="docEmphasis">northeast NE AM Main Jr. 5.1 .94 3 13</span>
<span class="docEmphasis">north NO Margot Weber 4.5 .89 5 9</span>
<span class="docEmphasis">central CT Ann Stephens 5.7 .94 5 13</span>
</pre>
<h5 id="ch04list11" class="docExampleTitle">Example 4.11 </h5>
<pre><span class="docEmphStrong">sed -n 's/^west/north/p' datafile</span>
<span class="docEmphasis">northern WE Sharon Gray 5.3 .97 5 23</span>
</pre>
<table cellSpacing="0" width="90%" border="1" align="center">
<tr>
<td>
<h2 class="docSidebarTitle">EXPLANATION</h2>
<p class="docText">The <span class="docEmphasis">s</span> command is for
substitution. The <span class="docEmphasis">-n</span> option with the
<span class="docEmphasis">p</span> flag at the end of the command tells
<span class="docEmphasis">sed</span> to print only those lines where the
substitution occurred; that is, if <span class="docEmphasis">west</span> is
found at the beginning of the line and is replaced with
<span class="docEmphasis">north,</span> just those lines are printed.</td>
</tr>
</table>
<h5 id="ch04list12" class="docExampleTitle">Example 4.12 </h5>
<pre><span class="docEmphStrong">sed 's/[0⌨️ 快捷键说明
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