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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 48] 48.5 leave: A Maddening Aid to Quitting on Time </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="1998-10-23T15:55:30Z"><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="ch48_01.htm"TITLE="48. Office Automation"><LINKREL="prev"HREF="ch48_04.htm"TITLE="48.4 Automatic Reminders and More: calendar "><LINKREL="next"HREF="ch48_06.htm"TITLE="48.6 Get Calendar for Any Month or Year: cal "></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="ch48_04.htm"TITLE="48.4 Automatic Reminders and More: calendar "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 48.4 Automatic Reminders and More: calendar "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 48<BR>Office Automation</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch48_06.htm"TITLE="48.6 Get Calendar for Any Month or Year: cal "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 48.6 Get Calendar for Any Month or Year: cal "BORDER="0"></A></TD></TR></TABLE>&nbsp;<HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-3960">48.5 leave: A Maddening Aid to Quitting on Time </A></H2><PCLASS="para"><ACLASS="indexterm"NAME="UPT-ART-3960-IX-LEAVE-PROGRAM"></A><CODECLASS="literal">Time</CODE> <CODECLASS="literal">to</CODE> <CODECLASS="literal">leave!</CODE>The message flashes across your screen, the terminal bell rings.You keep working.</P><PCLASS="para"><CODECLASS="literal">You're</CODE> <CODECLASS="literal">going</CODE> <CODECLASS="literal">to</CODE> <CODECLASS="literal">be</CODE> <CODECLASS="literal">late!</CODE>Another message, a minute later.Sheesh.Did your mother learn to use<SPANCLASS="link"><EMCLASS="emphasis">write</EM> (<ACLASS="linkend"HREF="ch01_33.htm"TITLE="UNIX Networking and Communications ">1.33</A>)</SPAN>,or what?</P><PCLASS="para">No.It's the <EMCLASS="emphasis">leave</EM> program that you started to remind you of a meeting.(A little while ago, it already told you that <CODECLASS="literal">You</CODE> <CODECLASS="literal">have</CODE><CODECLASS="literal">to</CODE> <CODECLASS="literal">leave</CODE> <CODECLASS="literal">in</CODE> <CODECLASS="literal">5</CODE> <CODECLASS="literal">minutes</CODE>.)If your system has <EMCLASS="emphasis">leave</EM>, you can start it in one of three ways: </P><ULCLASS="itemizedlist"><LICLASS="listitem"><PCLASS="para"><CODECLASS="userinput"><B>leave 1300</B></CODE> sets the alarm for 1:00 p.m.</P></LI><LICLASS="listitem"><PCLASS="para"><CODECLASS="userinput"><B>leave +30</B></CODE> sets the alarm for 30 minutes from now.</P></LI><LICLASS="listitem"><PCLASS="para">With no arguments, <CODECLASS="userinput"><B>leave</B></CODE> prompts you <CODECLASS="literal">When</CODE> <CODECLASS="literal">do</CODE> <CODECLASS="literal">you</CODE><CODECLASS="literal">have</CODE> <CODECLASS="literal">to</CODE> <CODECLASS="literal">leave?</CODE>You can type an answer like <CODECLASS="literal">1300</CODE> or <CODECLASS="literal">+30</CODE> above.Or, if you just pressRETURN,<EMCLASS="emphasis">leave</EM> will leave you alone.That's handy to put in your<SPANCLASS="link"><EMCLASS="emphasis">.login</EM> or <EMCLASS="emphasis">.profile</EM> (<ACLASS="linkend"HREF="ch02_02.htm"TITLE="Shell Setup Files-Which, Where, and Why ">2.2</A>)</SPAN>file.</P></LI></UL><PCLASS="para">When will it stop nagging you?When you log out, <EMCLASS="emphasis">leave</EM> stops automatically.Also, newer versions of <EMCLASS="emphasis">leave</EM> will quit after ten minutes, saying<CODECLASS="literal">That</CODE> <CODECLASS="literal">was</CODE> <CODECLASS="literal">the</CODE> <CODECLASS="literal">last</CODE> <CODECLASS="literal">time</CODE><CODECLASS="literal">I'll</CODE> <CODECLASS="literal">tell</CODE> <CODECLASS="literal">you.</CODE>  <CODECLASS="literal">Bye.</CODE>Older versions keep on forever.</P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-57937"></A>On some versions of <EMCLASS="emphasis">leave</EM>, you can't set an alarm for any time tomorrow(past midnight).But you can use<SPANCLASS="link"><EMCLASS="emphasis">sleep</EM> (<ACLASS="linkend"HREF="ch40_02.htm"TITLE="Waiting a Little While: sleep ">40.2</A>)</SPAN>to start the <EMCLASS="emphasis">leave</EM> past midnight.For example, maybe it's 10 p.m. now and you want to leave at 1 a.m.Midnight is two hours or 7200 seconds (60 x 60 x 2) from now.Adda fudge factor of 10 minutes (600 seconds) and type:</P><PCLASS="para"><TABLECLASS="screen.co"BORDER="1"><TR><THVALIGN="TOP"><PRECLASS="calloutlist"><ACLASS="co"HREF="ch13_07.htm"TITLE="13.7 The () Subshell Operators ">( )</A> &#13;</PRE></TH><TDVALIGN="TOP"><PRECLASS="screen">$ <CODECLASS="userinput"><B>(sleep 7800; leave 100) &amp;</B></CODE>1234</PRE></TD></TR></TABLE></P><PCLASS="para">You can also kill <EMCLASS="emphasis">leave</EM>-though you have to use the &quot;sure kill,&quot;<SPANCLASS="link">signal 9 (<ACLASS="linkend"HREF="ch38_08.htm"TITLE="What Are Signals? ">38.8</A>)</SPAN>.To see <EMCLASS="emphasis">leave</EM> lurking in the background and get its<SPANCLASS="link">PID (<ACLASS="linkend"HREF="ch38_03.htm"TITLE="Managing Processes: Overall Concepts ">38.3</A>)</SPAN>,you usually need the<SPANCLASS="link"><EMCLASS="emphasis">ps</EM> (<ACLASS="linkend"HREF="ch38_05.htm"TITLE="The ps Command ">38.5</A>)</SPAN><EMCLASS="emphasis">-x</EM> option.Piping through <EMCLASS="emphasis">grep leave</EM> will shorten the <EMCLASS="emphasis">ps</EM> output:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>ps x | grep leave</B></CODE> 6914 p3 S     0:00 leave19283 p3 R     0:01 grep leave% <CODECLASS="userinput"><B>kill -9 6914</B></CODE></PRE></BLOCKQUOTE></P><ACLASS="indexterm"NAME="AUTOID-57962"></A><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="ch48_04.htm"TITLE="48.4 Automatic Reminders and More: calendar "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 48.4 Automatic Reminders and More: calendar "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="ch48_06.htm"TITLE="48.6 Get Calendar for Any Month or Year: cal "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 48.6 Get Calendar for Any Month or Year: cal "BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172">48.4 Automatic Reminders and More: calendar </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">48.6 Get Calendar for Any Month or Year: cal </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 &amp; 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>
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