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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 15] 15.5 Matching All "Dot Files" with Wildcards</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="1998-08-04T21:37:24Z"><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_04.htm"TITLE="15.4 What if a Wildcard Doesn't Match? "><LINKREL="next"HREF="ch15_06.htm"TITLE="15.6 Maybe You Shouldn't Use Wildcards in Pathnames "></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_04.htm"TITLE="15.4 What if a Wildcard Doesn't Match? "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 15.4 What if a Wildcard Doesn't Match? "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="SECT1"HREF="ch15_06.htm"TITLE="15.6 Maybe You Shouldn't Use Wildcards in Pathnames "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 15.6 Maybe You Shouldn't Use Wildcards in Pathnames "BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-0125">15.5 Matching All "Dot Files" with Wildcards</A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-16317"></A><ACLASS="indexterm"NAME="AUTOID-16321"></A><ACLASS="indexterm"NAME="AUTOID-16325"></A><ACLASS="indexterm"NAME="AUTOID-16329"></A><ACLASS="indexterm"NAME="AUTOID-16332"></A>If you want to match all files in a directory whose names do not startwith a dot (<CODECLASS="literal">.</CODE>), it's easy: just use an asterisk (<CODECLASS="literal">*</CODE>).But what about files that <EMCLASS="emphasis">do</EM> start with a dot?That's harder because dot-asterisk (<CODECLASS="literal">.*</CODE>) matches the directory linksnamed <CODECLASS="literal">.</CODE> and <CODECLASS="literal">..</CODE> that are in every directory; youusually won't want to match those.</P><PCLASS="para">The Korn and some Bourne shells, as well as <EMCLASS="emphasis">bash</EM>, let you use thesequence <CODECLASS="literal">.[!.]*</CODE> to match all dot files, where <CODECLASS="literal">[!.]</CODE>means "anything but a dot."<EMCLASS="emphasis">tcsh</EM> understands <CODECLASS="literal">.[^.]*</CODE> instead.</P><PCLASS="para">Otherwise, what can you do?You can use <CODECLASS="literal">.??*</CODE>, which matches all filenames that start with adot and have at least two characters, but that doesn't match filenameslike <EMCLASS="emphasis">.a</EM> with just one character after the dot.Here's the answer:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">.[^A--0-^?]*</PRE></BLOCKQUOTE></P><PCLASS="para">That expression matches all filenames whose second character is in the<SPANCLASS="link">ASCII chart (<ACLASS="linkend"HREF="ch51_03.htm"TITLE="ASCII Characters: Listing and Getting Values ">51.3</A>)</SPAN>but isn't a dot or a slash (<CODECLASS="literal">/</CODE>).The range starts with CTRL-a(<CODECLASS="literal">^A</CODE> is an actual CTRL-a character, <EMCLASS="emphasis">not</EM> the two characters<CODECLASS="literal">^</CODE> and <CODECLASS="literal">A</CODE>) and runs through a dash (<CODECLASS="literal">-</CODE>).Then it covers the range from zero (<CODECLASS="literal">0</CODE>) through DEL orCTRL-<CODECLASS="literal">?</CODE>(make by pressing your DELETE or RUBOUTkey; you may have to type CTRL-vor a backslash (<CODECLASS="literal">\</CODE>) first).</P><PCLASS="para">Yuck - that's sort of complicated.To make it easy, I set that sequence in a shell variable named <EMCLASS="emphasis">dots</EM>from my<SPANCLASS="link">shell setup file (<ACLASS="linkend"HREF="ch02_02.htm"TITLE="Shell Setup Files-Which, Where, and Why ">2.2</A>)</SPAN>.Here are three versions; the third is for shells whose built-in<EMCLASS="emphasis">echo</EM> doesn't understand <CODECLASS="literal">\</CODE><CODECLASS="replaceable"><I>nnn</I></CODE> sequences:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen"> set dots=".[`echo Y-0-Z | tr YZ \\001\\177`]" <EMCLASS="emphasis">csh</EM>dots=".[`echo \\\\001-0-\\\\0177`]*" <EMCLASS="emphasis">sh, etc.</EM>dots=".[`echo Y-0-Z | tr YZ \\001\\177`]*" <EMCLASS="emphasis">sh with old echo</EM></PRE></BLOCKQUOTE></P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-16377"></A>(The <EMCLASS="emphasis">tr</EM>command in<SPANCLASS="link">backquotes (<ACLASS="linkend"HREF="ch09_16.htm"TITLE="Command Substitution ">9.16</A>)</SPAN>turns the expression <CODECLASS="literal">Y--0-Z</CODE>into the range with CTRL-a and DEL that we want.That keeps ugly, unprintable characters out of the <EMCLASS="emphasis">.cshrc</EM> file.See article<ACLASS="xref"HREF="ch45_35.htm"TITLE="Using a Control Character in a Script ">45.35</A>.)So, for example, I could move all files out of the current directory toanother directory by typing:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>mv * $dots</B></CODE> <CODECLASS="replaceable"><I>/somedir</I></CODE></PRE></BLOCKQUOTE></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_04.htm"TITLE="15.4 What if a Wildcard Doesn't Match? 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