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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 13] 13.15 What to Do with a Full Bit Bucket :-) </TITLE><METANAME="DC.title"CONTENT="UNIX Power Tools"><METANAME="DC.creator"CONTENT="Jerry Peek, Tim O'Reilly &amp; Mike Loukides"><METANAME="DC.publisher"CONTENT="O'Reilly &amp; Associates, Inc."><METANAME="DC.date"CONTENT="1998-08-04T21:36:54Z"><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="ch13_01.htm"TITLE="13. Redirecting Input and Output"><LINKREL="prev"HREF="ch13_14.htm"TITLE="13.14 What Can You Do with an Empty File? "><LINKREL="next"HREF="ch13_16.htm"TITLE="13.16 Store and Show Errors with logerrs "></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="ch13_14.htm"TITLE="13.14 What Can You Do with an Empty File? "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 13.14 What Can You Do with an Empty File? "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 13<BR>Redirecting Input and Output</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch13_16.htm"TITLE="13.16 Store and Show Errors with logerrs "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 13.16 Store and Show Errors with logerrs "BORDER="0"></A></TD></TR></TABLE>&nbsp;<HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-7900">13.15 What to Do with a Full Bit Bucket <CODECLASS="literal">:-)</CODE> </A></H2><ACLASS="indexterm"NAME="AUTOID-14898"></A><ACLASS="indexterm"NAME="AUTOID-14900"></A><PCLASS="para">[The techniques in this article should be performed carefully, andonly by a fully qualified and inexperienced system administrator.-JP]</P><DIVCLASS="msgset"><DIVCLASS="msgentry"><DIVCLASS="msg"><DIVCLASS="msgtext"><PCLASS="para"><BCLASS="msgentry.role">Q:</B> Our Sun SPARCstation 1+ 4.1 OW2 started running very slowly.When I logged out, I got the message&quot;/dev/null full: empty bit bucket.&quot;</P></DIV></DIV></DIV><DIVCLASS="msgentry"><DIVCLASS="msg"><DIVCLASS="msgtext"><PCLASS="para"><BCLASS="msgentry.role">A:</B> The problem is that <EMCLASS="emphasis">null</EM> is full.Your void space is no longer void; it's full up.</P></DIV></DIV></DIV></DIV><PCLASS="para"><BCLASS="emphasis.bold">The top ways to empty an overflowing bit bucket:</B></P><ULCLASS="itemizedlist"><LICLASS="listitem"><PCLASS="para">Open the computer.Look for the bit bucket, find the <EMCLASS="emphasis">red</EM> stopper at the bottom of itand open it over a <EMCLASS="emphasis">large</EM> wastebasket.</P></LI><LICLASS="listitem"><PCLASS="para">Take the ethernet terminator off.Type the command:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>cat /dev/null &gt; le0</B></CODE></PRE></BLOCKQUOTE></P><PCLASS="para">This spits the bits into the ether.</P></LI><LICLASS="listitem"><PCLASS="para">When you write to <EMCLASS="emphasis">/dev/null</EM>, the 0's (zeros) don't take up anyspace, but the 1's (ones) do.Try writing a file full of 0's to <EMCLASS="emphasis">/dev/null</EM>.Use binary 0, <EMCLASS="emphasis">not</EM> ASCII 0; ASCII 0 will start overfilling the partition.</P></LI><LICLASS="listitem"><PCLASS="para">This is a common problem <EMCLASS="emphasis">only</EM> if you use the computer.If you stop using it, it won't have many problems at all.Kick the other users off, too.</P></LI><LICLASS="listitem"><PCLASS="para">Run lots of C programs.They have null-terminated strings that will use up the extra bits in<EMCLASS="emphasis">/dev/null</EM>.</P></LI><LICLASS="listitem"><PCLASS="para">Consider upgrading to a byte bucket or even a word bucket.</P></LI><LICLASS="listitem"><PCLASS="para">Bring the computer to Mr. Goodwrench.He will drain the bit bucket, change the oil, and add windshield fluid,all in 29 minutes or less.Now that's a deal.</P></LI></UL><DIVCLASS="sect1info"><PCLASS="SECT1INFO">- <SPANCLASS="authorinitials">XX</SPAN> <SPANCLASS="bibliomisc">(We wish we knew who wrote this!)</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="ch13_14.htm"TITLE="13.14 What Can You Do with an Empty File? 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