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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 15] 15.10 Wildcards that Match Only Directories </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="1998-08-04T21:37:31Z"><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="ch15_01.htm"TITLE="15. Wildcards"><LINKREL="prev"HREF="ch15_09.htm"TITLE="15.9 nom: List Files that Don't Match a Wildcard "><LINKREL="next"HREF="ch16_01.htm"TITLE="16. Where Did I Put That?"></HEAD><BODYBGCOLOR="#FFFFFF"TEXT="#000000"><DIVCLASS="htmlnav"><H1><IMGSRC="gifs/smbanner.gif"ALT="UNIX Power Tools"USEMAP="#srchmap"BORDER="0"></H1><MAPNAME="srchmap"><AREASHAPE="RECT"COORDS="0,0,466,58"HREF="index.htm"ALT="UNIX Power Tools"><AREASHAPE="RECT"COORDS="467,0,514,18"HREF="jobjects/fsearch.htm"ALT="Search this book"></MAP><TABLEWIDTH="515"BORDER="0"CELLSPACING="0"CELLPADDING="0"><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch15_09.htm"TITLE="15.9 nom: List Files that Don't Match a Wildcard "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 15.9 nom: List Files that Don't Match a Wildcard "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 15<BR>Wildcards</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="CHAPTER"HREF="ch16_01.htm"TITLE="16. Where Did I Put That?"><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 16. Where Did I Put That?"BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-0225">15.10 Wildcards that Match Only Directories </A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-16598"></A>It's not news that the shell turns <CODECLASS="literal">.*</CODE> (dot asterisk) into every name in the current directory that startswith a dot: <EMCLASS="emphasis">.login</EM>, <EMCLASS="emphasis">.profile</EM>, <EMCLASS="emphasis">.bin</EM> (I name my directorythat way), and so on - including <CODECLASS="literal">.</CODE> and <CODECLASS="literal">..</CODE> too.</P><PCLASS="para">Also, many people know that the shell turns <CODECLASS="literal">*/.*</CODE>into a list of the dot files in subdirectories: <EMCLASS="emphasis">foo/.exrc</EM>,<EMCLASS="emphasis">foo/.hidden</EM>, <EMCLASS="emphasis">bar/.xxx</EM>-as well as <EMCLASS="emphasis">foo/.</EM>, <EMCLASS="emphasis">foo/..</EM>,<EMCLASS="emphasis">bar/.</EM>, and <EMCLASS="emphasis">bar/..</EM>, too.(If that surprises you, look at the wildcard pattern closely - or try iton your account with the <EMCLASS="emphasis">echo</EM> command: <CODECLASS="literal">echo</CODE> <CODECLASS="literal">*/.*</CODE>.)</P><PCLASS="para">What if you're trying to match just the subdirectory names, but not thefiles in them?The most direct way is: <CODECLASS="literal">*/.</CODE>-that matches <EMCLASS="emphasis">foo/.</EM>, <EMCLASS="emphasis">bar/.</EM>,and so on.The dot (<CODECLASS="literal">.</CODE>) entry in each directory<SPANCLASS="link">is a link to the directory itself (<ACLASS="linkend"HREF="ch18_02.htm"TITLE="What's Really in a Directory ">18.2</A>, <ACLASS="linkend"HREF="ch14_04.htm"TITLE="How Does UNIX Find Your Current Directory? ">14.4</A>)</SPAN>,so you can use it wherever you use the directory name.For example, to get a list of the names of your subdirectories, type:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">$ <CODECLASS="userinput"><B>ls -d */.</B></CODE>bar/. foo/.</PRE></BLOCKQUOTE></P><PCLASS="para">(The<SPANCLASS="link"><EMCLASS="emphasis">-d</EM> option (<ACLASS="linkend"HREF="ch16_08.htm"TITLE="The ls -d Option ">16.8</A>)</SPAN>tells <EMCLASS="emphasis">ls</EM> to list the names of directories, not their contents.)With some C shells (but not all), you don't need the trailing dot (<CODECLASS="literal">.</CODE>):</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>ls -d */</B></CODE>bar/ foo/</PRE></BLOCKQUOTE></P><PCLASS="para">(The shell passes the slashes (<CODECLASS="literal">/</CODE>) to <EMCLASS="emphasis">ls</EM>.So, if you use the <EMCLASS="emphasis">ls</EM><SPANCLASS="link"><EMCLASS="emphasis">-F</EM> option (<ACLASS="linkend"HREF="ch16_12.htm"TITLE="Useful ls Aliases ">16.12</A>)</SPAN>to put a slash after directorynames, the listing will show <EMCLASS="emphasis">two</EM> slashes after each directoryname.)</P><PCLASS="para">When matching directory names that start with a dot,the shells expand the <CODECLASS="literal">.*/</CODE> or <CODECLASS="literal">.*/.</CODE> and pass the result to<EMCLASS="emphasis">ls</EM>-so youreally don't need the <EMCLASS="emphasis">ls</EM><SPANCLASS="link"><EMCLASS="emphasis">-a</EM> option (<ACLASS="linkend"HREF="ch16_11.htm"TITLE="Showing Hidden Files with ls -A and -a ">16.11</A>)</SPAN>.The <EMCLASS="emphasis">-a</EM> is useful only whenyou ask <EMCLASS="emphasis">ls</EM> (not the shell) to read a directory and list the entries in it.You don't have to use <EMCLASS="emphasis">ls</EM>, of course.The<SPANCLASS="link"><EMCLASS="emphasis">echo</EM> (<ACLASS="linkend"HREF="ch08_06.htm"TITLE="Output Command-Line Arguments ">8.6</A>)</SPAN>command will show the same list more simply.</P><PCLASS="para">Here's another example: a Bourne shell loop that runs a command in eachsubdirectory of your home directory:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">for dir in $HOME/*/.do cd $dir ...<EMCLASS="emphasis">Do something</EM>...done</PRE></BLOCKQUOTE></P><PCLASS="para">That doesn't take care of subdirectories whose names begin with a dot,like my <EMCLASS="emphasis">.bin</EM>-but article<ACLASS="xref"HREF="ch15_05.htm"TITLE='Matching All "Dot Files" with Wildcards'>15.5</A>shows a way to do that too.</P><PCLASS="para">Article<ACLASS="xref"HREF="ch21_12.htm"TITLE="Copying Files to a Directory ">21.12</A>shows a related trick that doesn't involve the shell or wildcards:making a pathnamethat will match only a directory.<ACLASS="indexterm"NAME="AUTOID-16664"></A><ACLASS="indexterm"NAME="AUTOID-16665"></A></P><DIVCLASS="sect1info"><PCLASS="SECT1INFO">- <SPANCLASS="authorinitials">JP</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="ch15_09.htm"TITLE="15.9 nom: List Files that Don't Match a Wildcard "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 15.9 nom: List Files that Don't Match a Wildcard "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="CHAPTER"HREF="ch16_01.htm"TITLE="16. 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