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diff --git a/slackbook/html/file-commands-output.html b/slackbook/html/file-commands-output.html new file mode 100644 index 00000000..e2419b27 --- /dev/null +++ b/slackbook/html/file-commands-output.html @@ -0,0 +1,147 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml"> +<head> +<meta name="generator" content="HTML Tidy, see www.w3.org" /> +<title>Simple Output: cat and echo</title> +<meta name="GENERATOR" content="Modular DocBook HTML Stylesheet Version 1.7" /> +<link rel="HOME" title="Slackware Linux Essentials" href="index.html" /> +<link rel="UP" title="Handling Files and Directories" href="file-commands.html" /> +<link rel="PREVIOUS" title="Pagers: more, less, and most" +href="file-commands-pagers.html" /> +<link rel="NEXT" title="Creation: touch and mkdir" href="file-commands-creation.html" /> +<link rel="STYLESHEET" type="text/css" href="docbook.css" /> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> +</head> +<body class="SECT1" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#840084" +alink="#0000FF"> +<div class="NAVHEADER"> +<table summary="Header navigation table" width="100%" border="0" cellpadding="0" +cellspacing="0"> +<tr> +<th colspan="3" align="center">Slackware Linux Essentials</th> +</tr> + +<tr> +<td width="10%" align="left" valign="bottom"><a href="file-commands-pagers.html" +accesskey="P">Prev</a></td> +<td width="80%" align="center" valign="bottom">Chapter 10 Handling Files and +Directories</td> +<td width="10%" align="right" valign="bottom"><a href="file-commands-creation.html" +accesskey="N">Next</a></td> +</tr> +</table> + +<hr align="LEFT" width="100%" /> +</div> + +<div class="SECT1"> +<h1 class="SECT1"><a id="FILE-COMMANDS-OUTPUT" name="FILE-COMMANDS-OUTPUT">10.3 Simple +Output: <tt class="COMMAND">cat</tt> and <tt class="COMMAND">echo</tt></a></h1> + +<div class="SECT2"> +<h2 class="SECT2"><a id="AEN3559" name="AEN3559">10.3.1 <tt +class="COMMAND">cat</tt></a></h2> + +<p><tt class="COMMAND">cat</tt>(1) is short for “concatenate”. It was +originally designed to merge text files into one, but can be used for many other +purposes.</p> + +<p>To merge two or more files into one, you simply list the files after the <tt +class="COMMAND">cat</tt> command and then redirect the new output to a file. <tt +class="COMMAND">cat</tt> works with standard input and standard output, so you have to +use the shell redirection characters. For example:</p> + +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="SCREEN"> +<samp class="PROMPT">%</samp> <kbd +class="USERINPUT">cat file1 file2 file3 > bigfile</kbd> +</pre> +</td> +</tr> +</table> + +<p>This command takes the contents of <tt class="FILENAME">file1</tt>, <tt +class="FILENAME">file2</tt>, and <tt class="FILENAME">file3</tt> and merges it all +together. The new output is sent to standard out.</p> + +<p>One can also use <tt class="COMMAND">cat</tt> to display files. Many people <tt +class="COMMAND">cat</tt> text files through the <tt class="COMMAND">more</tt> or <tt +class="COMMAND">less</tt> commands, like this:</p> + +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="SCREEN"> +<samp class="PROMPT">%</samp> <kbd class="USERINPUT">cat file1 | more</kbd> +</pre> +</td> +</tr> +</table> + +<p>That will display the <tt class="FILENAME">file1</tt> file and pipe it through the <tt +class="COMMAND">more</tt> command so that you only get one screen at a time.</p> + +<p>Another common use for <tt class="COMMAND">cat</tt> is copying files. You can copy any +file around with <tt class="COMMAND">cat</tt>, like this:</p> + +<table border="0" bgcolor="#E0E0E0" width="100%"> +<tr> +<td> +<pre class="SCREEN"> +<samp class="PROMPT">%</samp> <kbd class="USERINPUT">cat /bin/bash > ~/mybash</kbd> +</pre> +</td> +</tr> +</table> + +<p>The <tt class="COMMAND">/bin/bash</tt> program is copied to your home directory and +named <tt class="FILENAME">mybash</tt>.</p> + +<p><tt class="COMMAND">cat</tt> has many uses and the ones discussed here are just a few. +Since <tt class="COMMAND">cat</tt> makes extensive use of standard input and standard +output, it is ideal for use in shell scripts or part of other complex commands.</p> +</div> + +<div class="SECT2"> +<h2 class="SECT2"><a id="AEN3603" name="AEN3603">10.3.2 <tt +class="COMMAND">echo</tt></a></h2> + +<p>The <tt class="COMMAND">echo</tt>(1) command displays the specified text on the +screen. You specify the string to display after the <tt class="COMMAND">echo</tt> +command. By default <tt class="COMMAND">echo</tt> will display the string and print a +newline character after it. You can pass the <var class="OPTION">-n</var> option to +suppress the printing of the newline. The <var class="OPTION">-e</var> option will cause +<tt class="COMMAND">echo</tt> to search for escape characters in the string and execute +them.</p> +</div> +</div> + +<div class="NAVFOOTER"> +<hr align="LEFT" width="100%" /> +<table summary="Footer navigation table" width="100%" border="0" cellpadding="0" +cellspacing="0"> +<tr> +<td width="33%" align="left" valign="top"><a href="file-commands-pagers.html" +accesskey="P">Prev</a></td> +<td width="34%" align="center" valign="top"><a href="index.html" +accesskey="H">Home</a></td> +<td width="33%" align="right" valign="top"><a href="file-commands-creation.html" +accesskey="N">Next</a></td> +</tr> + +<tr> +<td width="33%" align="left" valign="top">Pagers: <tt class="COMMAND">more</tt>, <tt +class="COMMAND">less</tt>, and <tt class="COMMAND">most</tt></td> +<td width="34%" align="center" valign="top"><a href="file-commands.html" +accesskey="U">Up</a></td> +<td width="33%" align="right" valign="top">Creation: <tt class="COMMAND">touch</tt> and +<tt class="COMMAND">mkdir</tt></td> +</tr> +</table> +</div> +</body> +</html> + |