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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 24] 24.4 Save Space with a Link </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="1998-08-04T21:41:30Z"><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="ch24_01.htm"TITLE="24. Other Ways to Get Disk Space"><LINKREL="prev"HREF="ch24_03.htm"TITLE="24.3 Unlinking Open Files Isn't a Good Idea "><LINKREL="next"HREF="ch24_05.htm"TITLE="24.5 Limiting File Sizes "></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="ch24_03.htm"TITLE="24.3 Unlinking Open Files Isn't a Good Idea "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 24.3 Unlinking Open Files Isn't a Good Idea "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 24<BR>Other Ways to Get Disk Space</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch24_05.htm"TITLE="24.5 Limiting File Sizes "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 24.5 Limiting File Sizes "BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-6940">24.4 Save Space with a Link </A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-26295"></A><ACLASS="indexterm"NAME="AUTOID-26298"></A><ACLASS="indexterm"NAME="AUTOID-26301"></A>You might have copies of the same file in several directories because:</P><ULCLASS="itemizedlist"><LICLASS="listitem"><PCLASS="para">Several different users need to read it (a data file, a program setup file, atelephone list, etc.).</P></LI><LICLASS="listitem"><PCLASS="para">It's a program that more than one person wants to use.For some reason, you don't want to keep one central copy and put its directoryin your<SPANCLASS="link">search path (<ACLASS="linkend"HREF="ch08_07.htm"TITLE="Setting Your Search Path ">8.7</A>)</SPAN>.</P></LI><LICLASS="listitem"><PCLASS="para">The file has a strange name or it's in a directory you don't usually use.You want a name that's easier to type, but you can't use <EMCLASS="emphasis">mv</EM>.</P></LI></UL><TABLECLASS="para.programreference"BORDER="1"><TR><THVALIGN="TOP"><ACLASS="programreference"HREF="examples/index.htm"TITLE="ln">ln</A><BR></TH><TDVALIGN="TOP">Instead of running <EMCLASS="emphasis">cp</EM>, think about <EMCLASS="emphasis">ln</EM>.(Your system should have <EMCLASS="emphasis">ln</EM>.But it comes with the GNU fileutils, so it's on the Power Toolsdisc too.)There are lots of advantages to<SPANCLASS="link">links (<ACLASS="linkend"HREF="ch18_03.htm"TITLE="Files with Two or More Names">18.3</A>)</SPAN>.One big advantage of hard links is that they don't use any disk space.[1]The bigger the file, the more space you save with a link.A symbolic link always takes some disk space, so a hard link might be better(unless you have to link across filesystems so hard links can't be used).</TD></TR></TABLE><BLOCKQUOTECLASS="footnote"><PCLASS="para">[1] The link entry takes a few characters in the directory where you makethe link.Unless this makes the directory occupy anotherdisk block,the space available on the disk doesn't change.</P></BLOCKQUOTE><PCLASS="para">Some people don't use links because they think all links to a file need tohave the same name.That's not true.A link can be named <EMCLASS="emphasis">myfile</EM> in one directory and <EMCLASS="emphasis">file.allan</EM> inanother directory-UNIX keeps it all straight.</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="ch24_03.htm"TITLE="24.3 Unlinking Open Files Isn't a Good Idea 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