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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 16] 16.12 Useful ls Aliases </TITLE><METANAME="DC.title"CONTENT="UNIX Power Tools"><METANAME="DC.creator"CONTENT="Jerry Peek, Tim O'Reilly & Mike Loukides"><METANAME="DC.publisher"CONTENT="O'Reilly & Associates, Inc."><METANAME="DC.date"CONTENT="1998-08-04T21:37:46Z"><METANAME="DC.type"CONTENT="Text.Monograph"><METANAME="DC.format"CONTENT="text/html"SCHEME="MIME"><METANAME="DC.source"CONTENT="1-56592-260-3"SCHEME="ISBN"><METANAME="DC.language"CONTENT="en-US"><METANAME="generator"CONTENT="Jade 1.1/O'Reilly DocBook 3.0 to HTML 4.0"><LINKREV="made"HREF="mailto:online-books@oreilly.com"TITLE="Online Books Comments"><LINKREL="up"HREF="ch16_01.htm"TITLE="16. Where Did I Put That?"><LINKREL="prev"HREF="ch16_11.htm"TITLE="16.11 Showing Hidden Files with ls -A and -a "><LINKREL="next"HREF="ch16_13.htm"TITLE="16.13 Can't Access a File? 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Look for Spaces in the Name "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 16.13 Can't Access a File? Look for Spaces in the Name "BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-1540">16.12 Useful ls Aliases </A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-17200"></A><ACLASS="indexterm"NAME="AUTOID-17203"></A>Because <EMCLASS="emphasis">ls</EM> is one of the most commonly used UNIX commandsand provides numerous options, it's a good idea to create aliasesfor the display formats that best suit your needs. For example,many users <EMCLASS="emphasis">always</EM> want to know about their "hidden" files.That's reasonable - they're just as important as any other files youhave. In some cases, they can grow to take up lots of room (forexample, some editors hide backup files), so it's worth being aware ofthem.</P><PCLASS="para">Rather than typing <CODECLASS="literal">ls -a</CODE> every time, you can create a convenientalias that supplies the<SPANCLASS="link"><EMCLASS="emphasis">-a</EM> or <EMCLASS="emphasis">-A</EM> option (<ACLASS="linkend"HREF="ch16_11.htm"TITLE="Showing Hidden Files with ls -A and -a ">16.11</A>)</SPAN>automatically:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">alias la "ls -aF"</PRE></BLOCKQUOTE></P><PCLASS="para">or:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">alias la "ls -AF"</PRE></BLOCKQUOTE></P><PCLASS="para">Two things to note here. First, I recommend using <EMCLASS="emphasis">la</EM> as thename of the alias, rather than just renaming <EMCLASS="emphasis">ls</EM>. I personallythink it's dangerous to hide the pure, unadulterated commandunderneath an alias; it's better to pick a new name, and getused tousing that name. If you ever need the original <EMCLASS="emphasis">ls</EM> for somereason, you'll be able to get at it without problems.</P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-17223"></A>Second, what's with the <EMCLASS="emphasis">-F</EM> option? I just threw it in to see if youwere paying attention. It's actually quite useful; many users add itto their <EMCLASS="emphasis">ls</EM> aliases. The <EMCLASS="emphasis">-F</EM> option shows you the <EMCLASS="emphasis">type</EM> offile in each directory by printing an extra character after eachfilename.<ACLASS="xref"HREF="ch16_12.htm#UPT-ART-1540-TAB-0"TITLE="Filename Types Listed by ls -F">Table 16.1</A>lists what the extra character can be.</P><TABLECLASS="table"><CAPTIONCLASS="table"><ACLASS="title"NAME="UPT-ART-1540-TAB-0">Table 16.1: Filename Types Listed by ls -F</A></CAPTION><THEADCLASS="thead"><TRCLASS="row"VALIGN="TOP"><THCLASS="entry"ALIGN="LEFT"ROWSPAN="1"COLSPAN="1">Character</TH><THCLASS="entry"ALIGN="LEFT"ROWSPAN="1"COLSPAN="1">Definition</TH></TR></THEAD><TBODYCLASS="tbody"><TRCLASS="row"VALIGN="TOP"><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">(nothing)</TD><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">The file is a regular file.</TD></TR><TRCLASS="row"VALIGN="TOP"><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">*</TD><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">The file is an executable.</TD></TR><TRCLASS="row"VALIGN="TOP"><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">/</TD><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">The file is a directory.</TD></TR><TRCLASS="row"VALIGN="TOP"><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">@</TD><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">The file is a <SPANCLASS="link">symbolic link (<ACLASS="linkend"HREF="ch18_04.htm"TITLE="More About Links ">18.4</A>)</SPAN>.</TD></TR><TRCLASS="row"VALIGN="TOP"><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">=</TD><TDCLASS="entry"ROWSPAN="1"COLSPAN="1">The file is a "socket" (don't worry about this).</TD></TR></TBODY></TABLE><PCLASS="para">For example:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>la </B></CODE><EMCLASS="emphasis">Alias includes -F functionality</EM>.cshrc .login Mail/ performance/.emacs .mailrc mail.txt powertools@</PRE></BLOCKQUOTE></P><PCLASS="para">This says that <EMCLASS="emphasis">Mail</EM> and <EMCLASS="emphasis">performance</EM> are directories.<EMCLASS="emphasis">powertools</EM> is a symbolic link (<EMCLASS="emphasis">ls -l</EM> will show you whatit's linked to). There are no executables or "sockets" in thisdirectory.</P><PCLASS="para">You may want this version instead:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">alias la ls -aFC</PRE></BLOCKQUOTE></P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-17269"></A>The <EMCLASS="emphasis">-C</EM> option lists the files in multiple columns. This option isn't neededon systems where multi-column output is the normal behavior(for example, in SVR4). Note, however, that when piped to another command, <EMCLASS="emphasis">ls</EM> output is single-column unless <EMCLASS="emphasis">-C</EM> is used.For example, use <CODECLASS="literal">ls -C | more</CODE> to preserve multiple columns.</P><PCLASS="para">Finally, if you often need the full listing, use the alias:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">alias ll ls -l</PRE></BLOCKQUOTE></P><PCLASS="para">This alias may not seem like much of a shortcut until after you've typed ita dozen times. In addition, it's easy to remember as "long listing."Some UNIX systems even include <EMCLASS="emphasis">ll</EM> as a regular command.</P><DIVCLASS="sect1info"><PCLASS="SECT1INFO">- <SPANCLASS="authorinitials">DG</SPAN>, <SPANCLASS="authorinitials">ML</SPAN></P></DIV></DIV><DIVCLASS="htmlnav"><P></P><HRALIGN="LEFT"WIDTH="515"TITLE="footer"><TABLEWIDTH="515"BORDER="0"CELLSPACING="0"CELLPADDING="0"><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch16_11.htm"TITLE="16.11 Showing Hidden Files with ls -A and -a "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 16.11 Showing Hidden Files with ls -A and -a "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><ACLASS="book"HREF="index.htm"TITLE="UNIX Power Tools"><IMGSRC="gifs/txthome.gif"SRC="gifs/txthome.gif"ALT="UNIX Power Tools"BORDER="0"></A></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch16_13.htm"TITLE="16.13 Can't Access a File? 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