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Posted to dev@ant.apache.org by bo...@apache.org on 2003/08/14 18:16:21 UTC
cvs commit: ant/xdocs faq.xml
bodewig 2003/08/14 09:16:21
Modified: docs faq.html
xdocs faq.xml
Log:
Avoid "useless use of cat" award by using a real world example.
Revision Changes Path
1.76 +10 -9 ant/docs/faq.html
Index: faq.html
===================================================================
RCS file: /home/cvs/ant/docs/faq.html,v
retrieving revision 1.75
retrieving revision 1.76
diff -u -r1.75 -r1.76
--- faq.html 13 Aug 2003 06:11:58 -0000 1.75
+++ faq.html 14 Aug 2003 16:16:20 -0000 1.76
@@ -673,26 +673,27 @@
How do I redirect standard input or standard output
in the <code><exec></code> task?
</p>
- <p>Say you want to redirect the standard input stream of the
- <code>cat</code> command to read from a file, something
+ <p>Say you want to redirect the standard output stream of the
+ <code>m4</code> command to write to a file, something
like:</p>
<pre class="code">
-shell-prompt> cat < foo
+shell-prompt> m4 foo.m4 > foo
</pre>
<p>and try to translate it into</p>
<pre class="code">
-<exec executable="cat">
- <arg value="&lt;" />
- <arg value="foo" />
+<exec executable="m4">
+ <arg value="foo.m4"/>
+ <arg value="&gt;"/>
+ <arg value="foo"/>
</exec>
</pre>
- <p>This will not do what you expect. The input redirection is
+ <p>This will not do what you expect. The output redirection is
performed by your shell, not the command itself, so this
should read:</p>
<pre class="code">
<exec executable="/bin/sh">
<arg value="-c" />
- <arg value="cat &lt; foo" />
+ <arg value="m4 foo.m4 &gt; foo" />
</exec>
</pre>
<p>Note that you must use the <code>value</code> attribute of
@@ -701,7 +702,7 @@
you can use:</p>
<pre class="code">
<exec executable="/bin/sh">
- <arg line='-c "cat &lt; foo"'/>
+ <arg line='-c "m4 foo.m4 &gt; foo"'/>
</exec>
</pre>
<p>Note the double-quotes nested inside the single-quotes.</p>
1.37 +10 -9 ant/xdocs/faq.xml
Index: faq.xml
===================================================================
RCS file: /home/cvs/ant/xdocs/faq.xml,v
retrieving revision 1.36
retrieving revision 1.37
diff -u -r1.36 -r1.37
--- faq.xml 13 Aug 2003 06:11:58 -0000 1.36
+++ faq.xml 14 Aug 2003 16:16:21 -0000 1.37
@@ -313,31 +313,32 @@
<question>How do I redirect standard input or standard output
in the <code><exec></code> task?</question>
<answer>
- <p>Say you want to redirect the standard input stream of the
- <code>cat</code> command to read from a file, something
+ <p>Say you want to redirect the standard output stream of the
+ <code>m4</code> command to write to a file, something
like:</p>
<source><![CDATA[
-shell-prompt> cat < foo
+shell-prompt> m4 foo.m4 > foo
]]></source>
<p>and try to translate it into</p>
<source><![CDATA[
-<exec executable="cat">
- <arg value="<" />
- <arg value="foo" />
+<exec executable="m4">
+ <arg value="foo.m4"/>
+ <arg value=">"/>
+ <arg value="foo"/>
</exec>
]]></source>
- <p>This will not do what you expect. The input redirection is
+ <p>This will not do what you expect. The output redirection is
performed by your shell, not the command itself, so this
should read:</p>
<source><![CDATA[
<exec executable="/bin/sh">
<arg value="-c" />
- <arg value="cat < foo" />
+ <arg value="m4 foo.m4 > foo" />
</exec>
]]></source>
@@ -347,7 +348,7 @@
you can use:</p>
<source><![CDATA[
<exec executable="/bin/sh">
- <arg line='-c "cat < foo"'/>
+ <arg line='-c "m4 foo.m4 > foo"'/>
</exec>
]]></source>
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