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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 17] 17.17 Duplicating a Directory Tree (No Pathnames with find {} Operator)</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="1998-08-04T21:38:32Z"><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="ch17_01.htm"TITLE="17. Finding Files with find"><LINKREL="prev"HREF="ch17_16.htm"TITLE="17.16 Searching by Owner and Group "><LINKREL="next"HREF="ch17_18.htm"TITLE='17.18 Using "Fast find"'></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="ch17_16.htm"TITLE="17.16 Searching by Owner and Group "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 17.16 Searching by Owner and Group "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 17<BR>Finding Files with find</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch17_18.htm"TITLE='17.18 Using "Fast find"'><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT='Next: 17.18 Using "Fast find"'BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-0288">17.17 Duplicating a Directory Tree (No Pathnames with find {} Operator)</A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-19330"></A><ACLASS="indexterm"NAME="AUTOID-19333"></A><ACLASS="indexterm"NAME="AUTOID-19336"></A><ACLASS="indexterm"NAME="AUTOID-19339"></A>The <EMCLASS="emphasis">find</EM> operator <CODECLASS="literal">{}</CODE>, used with the<SPANCLASS="link"><EMCLASS="emphasis">-exec</EM> (<ACLASS="linkend"HREF="ch17_10.htm"TITLE="Running Commands on What You Find ">17.10</A>)</SPAN>operator, only works when it's separated fromother arguments by white space.So, for example, the following command will <EMCLASS="emphasis">not</EM> do what you thoughtit would:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>find . -type d -exec mkdir /usr/project/{} \;</B></CODE></PRE></BLOCKQUOTE></P><PCLASS="para">You might have thought this command wouldmake a duplicate set of - pty) directories, from thecurrent directory and down, starting at the directory <EMCLASS="emphasis">/usr/project</EM>.For instance, when the <EMCLASS="emphasis">find</EM> command finds the directory <EMCLASS="emphasis">./adir</EM>,you would have it execute <CODECLASS="literal">mkdir</CODE> <CODECLASS="literal">/usr/project/./adir</CODE><SPANCLASS="link">(ignore the dot; the result is <EMCLASS="emphasis">/usr/project/adir</EM>) (<ACLASS="linkend"HREF="ch01_21.htm"TITLE="Making Pathnames ">1.21</A>)</SPAN>.</P><PCLASS="para">That doesn't work because <EMCLASS="emphasis">find</EM> doesn't recognize the <CODECLASS="literal">{}</CODE> in thepathname.The trick is to pass the directory names to <SPANCLASS="link"><EMCLASS="emphasis">sed</EM> (<ACLASS="linkend"HREF="ch34_24.htm"TITLE="Quick Reference: sed ">34.24</A>)</SPAN>,which substitutes in the leading pathname:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>find . -type d -print | sed 's@^@/usr/project/@' | xargs mkdir</B></CODE>% <CODECLASS="userinput"><B>find . -type d -print | sed 's@^@mkdir @' | (cd /usr/project; sh)</B></CODE></PRE></BLOCKQUOTE></P><PCLASS="para">Let's start with the first example.Given a list of directory names, <EMCLASS="emphasis">sed</EM>substitutes the desired path to that directory at the beginning of the linebefore passing the completed filenames to <SPANCLASS="link"><EMCLASS="emphasis">xargs</EM> (<ACLASS="linkend"HREF="ch09_21.htm"TITLE="Handle Too-Long Command Lines with xargs ">9.21</A>)</SPAN>and <EMCLASS="emphasis">mkdir</EM>.An<SPANCLASS="link"><CODECLASS="literal">@</CODE> is used as a <EMCLASS="emphasis">sed</EM> delimiter (<ACLASS="linkend"HREF="ch34_07.htm"TITLE="Delimiting a Regular Expression ">34.7</A>)</SPAN>because slashes (/) are needed in the actual text of the substitution.If you don't have <EMCLASS="emphasis">xargs</EM>, try the second example.It uses <EMCLASS="emphasis">sed</EM> to insert the <EMCLASS="emphasis">mkdir</EM> command, then changesto the target directory in a<SPANCLASS="link">subshell (<ACLASS="linkend"HREF="ch13_07.htm"TITLE="The () Subshell Operators ">13.7</A>)</SPAN>where the<EMCLASS="emphasis">mkdir</EM> commands will actually be executed.</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="ch17_16.htm"TITLE="17.16 Searching by Owner and Group "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 17.16 Searching by Owner and Group "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="ch17_18.htm"TITLE='17.18 Using "Fast find"'><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT='Next: 17.18 Using "Fast find"'BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172">17.16 Searching by Owner and Group </TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><ACLASS="index"HREF="index/idx_0.htm"TITLE="Book Index"><IMGSRC="gifs/index.gif"SRC="gifs/index.gif"ALT="Book Index"BORDER="0"></A></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172">17.18 Using "Fast find"</TD></TR></TABLE><HRALIGN="LEFT"WIDTH="515"TITLE="footer"><IMGSRC="gifs/smnavbar.gif"SRC="gifs/smnavbar.gif"USEMAP="#map"BORDER="0"ALT="The UNIX CD Bookshelf Navigation"><MAPNAME="map"><AREASHAPE="RECT"COORDS="0,0,73,21"HREF="../index.htm"ALT="The UNIX CD Bookshelf"><AREASHAPE="RECT"COORDS="74,0,163,21"HREF="index.htm"ALT="UNIX Power Tools"><AREASHAPE="RECT"COORDS="164,0,257,21"HREF="../unixnut/index.htm"ALT="UNIX in a Nutshell"><AREASHAPE="RECT"COORDS="258,0,321,21"HREF="../vi/index.htm"ALT="Learning the vi Editor"><AREASHAPE="RECT"COORDS="322,0,378,21"HREF="../sedawk/index.htm"ALT="sed & awk"><AREASHAPE="RECT"COORDS="379,0,438,21"HREF="../ksh/index.htm"ALT="Learning the Korn Shell"><AREASHAPE="RECT"COORDS="439,0,514,21"HREF="../lrnunix/index.htm"ALT="Learning the UNIX Operating System"></MAP></DIV></BODY></HTML>⌨️ 快捷键说明
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