From d45e83060849ab8547342f24954eefa1440e688a Mon Sep 17 00:00:00 2001
From: Martin Goik <goik@hdm-stuttgart.de>
Date: Thu, 12 May 2016 21:53:59 +0200
Subject: [PATCH] Small extension hint
---
Doc/Sd1/appendix.xml | 90 +++++++++++++++++++++++++++++++++++++++-----
1 file changed, 80 insertions(+), 10 deletions(-)
diff --git a/Doc/Sd1/appendix.xml b/Doc/Sd1/appendix.xml
index 9cd98d225..ed54d613f 100644
--- a/Doc/Sd1/appendix.xml
+++ b/Doc/Sd1/appendix.xml
@@ -313,13 +313,13 @@
<title>Poor man's <xref linkend="glo_UNIX"/> <command
xlink:href="http://linux.die.net/man/1/grep">grep</command>.</title>
- <para>The <xref linkend="glo_UNIX"/> operating system provides the
+ <para>The <xref linkend="glo_UNIX"/> operating system provides a command
<command xlink:href="http://linux.die.net/man/1/grep">grep</command>
- command which allows for retrieving occurrences of given strings in text
- files. We consider an example text file <filename>input.txt</filename>
+ which allows for retrieving occurrences of a given string in text files.
+ We consider an example text file <filename>input.txt</filename>
containing four lines:</para>
- <programlisting language="none" linenumbering="unnumbered">Roses are nice flowers.
+ <programlisting language="none" linenumbering="numbered">Roses are nice flowers.
Red wine is tasty
The red cross acts worldwide
Mayflower used to be a ship.</programlisting>
@@ -328,7 +328,7 @@ Mayflower used to be a ship.</programlisting>
occurrence of the string <quote>flower</quote> being contained in lines
1 and 4:</para>
- <programlisting language="none">>grep <emphasis role="bold">flower</emphasis> input.txt
+ <programlisting language="none">> grep <emphasis role="bold">flower</emphasis> input.txt
Roses are nice <emphasis role="bold">flower</emphasis>s.
May<emphasis role="bold">flower</emphasis> used to be a ship.</programlisting>
@@ -338,18 +338,88 @@ May<emphasis role="bold">flower</emphasis> used to be a ship.</programlisting>
output. Adding the command line option <option>-i</option> allows for
case insensitive searches:</para>
- <programlisting language="none" linenumbering="unnumbered">>grep <option>-i</option> <emphasis
- role="bold">red</emphasis> input.txt
+ <programlisting language="none" linenumbering="unnumbered">> grep <option>-i</option> <emphasis
+ role="bold">red</emphasis> input.txt
<emphasis role="bold">Red</emphasis> wine is tasty
The <emphasis role="bold">red</emphasis> cross acts worldwide</programlisting>
<para>This time all possible variants like <quote>Red</quote>,
- <quote>red</quote>, <quote>RED</quote> and so on will match. </para>
+ <quote>red</quote>, <quote>RED</quote> and so on will match.</para>
<para><command
xlink:href="http://linux.die.net/man/1/grep">grep</command> also allows
- for searching multiple files. Consider another text file
- second.txt:</para>
+ for searching multiple files. Consider a second file
+ <filename>inputSecond.txt</filename>:</para>
+
+ <programlisting language="none" linenumbering="numbered">Errors will show up in red.
+Let's start bug fixing</programlisting>
+
+ <para>We may search for case insensitive (<option>-i</option> again)
+ appearances of <quote>red</quote> within both files:</para>
+
+ <programlisting language="none" linenumbering="unnumbered">> grep -i <emphasis
+ role="bold">red</emphasis> input.txt inputSecond.txt
+input.txt:<emphasis role="bold">Red</emphasis> wine is tasty
+input.txt:The <emphasis role="bold">red</emphasis> cross acts worldwide
+inputSecond.txt:Errors will show up in <emphasis role="bold">red</emphasis>.</programlisting>
+
+ <para>Finally the <option>-l</option> option will filter individual
+ appearances just showing filenames containing matches:</para>
+
+ <programlisting language="none">> grep -l Red input.txt inputSecond.txt
+input.txt</programlisting>
+
+ <para>In contrast a case insensitive search combining both
+ <option>-i</option> and <option>-l</option> options yields:</para>
+
+ <programlisting language="none">> grep -i -l Red input.txt inputSecond.txt
+input.txt
+inputSecond.txt</programlisting>
+
+ <para>The <command
+ xlink:href="http://linux.die.net/man/1/grep">grep</command> command may
+ read its input from standard input allowing for <link
+ xlink:href="https://en.wikipedia.org/wiki/Pipeline_(Unix)">pipes</link>.
+ This way another command's output feeds into a subsequently executed
+ command. As an example consider a recursive search for HTML files using
+ the <link xlink:href="http://linux.die.net/man/1/find">find</link>
+ command:</para>
+
+ <programlisting language="none">> find . -name \*.html
+./Sd1/Wc/wc/Testdata/input.html
+./Sda1/rdbmsXml2Html/TestData/climbingprice.html
+./Sda1/NoCast/src/main/resources/gallery.html
+./Sda1/Jdom/Html2Html/src/main/resources/imageExampleNew.html
+./Sda1/Jdom/Html2Html/src/main/resources/imageExample.html
+./Sda1/VerifyImgAccess/fileextref.html</programlisting>
+
+ <para>We want to restrict the above list to pathnames containing the
+ string <quote>Example</quote>. This may be achieved by <link
+ xlink:href="https://en.wikipedia.org/wiki/Pipeline_(Unix)">piping</link>
+ the <link xlink:href="http://linux.die.net/man/1/find">find</link>
+ command's output as input to <command
+ xlink:href="http://linux.die.net/man/1/grep">grep</command> searching
+ for the occurrence of the string <quote>Example</quote>. Technically
+ both processes get connected by means of the pipe symbol
+ <quote>|</quote>:</para>
+
+ <programlisting language="none">> find . -name \*.html|grep Example
+./Sda1/Jdom/Html2Html/src/main/resources/imageExampleNew.html
+./Sda1/Jdom/Html2Html/src/main/resources/imageExample.html</programlisting>
+
+ <tip>
+ <para/>
+
+ <orderedlist>
+ <listitem>
+ <para/>
+ </listitem>
+
+ <listitem>
+ <para/>
+ </listitem>
+ </orderedlist>
+ </tip>
</section>
<section xml:id="sd1ProjectSieveErathostenes">
--
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