📄 ch38_17.htm
字号:
<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 38] 38.17 Automatically Kill Background Processes on Logout in csh</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="1998-08-04T21:50:01Z"><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="ch38_01.htm"TITLE="38. Starting, Stopping, and Killing Processes"><LINKREL="prev"HREF="ch38_16.htm"TITLE="38.16 Why You Can't Kill a Zombie "><LINKREL="next"HREF="ch38_18.htm"TITLE="38.18 nohup "></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="ch38_16.htm"TITLE="38.16 Why You Can't Kill a Zombie "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 38.16 Why You Can't Kill a Zombie "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 38<BR>Starting, Stopping, and Killing Processes</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch38_18.htm"TITLE="38.18 nohup "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 38.18 nohup "BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-0256">38.17 Automatically Kill Background Processes on Logout in csh</A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-43393"></A><ACLASS="indexterm"NAME="AUTOID-43396"></A><ACLASS="indexterm"NAME="AUTOID-43399"></A>In many versions of the Bourne shell,<SPANCLASS="link">background processes (<ACLASS="linkend"HREF="ch01_26.htm"TITLE="What a Multiuser System Can Do for You ">1.26</A>)</SPAN>are automatically killed with a HANGUP signal (signal 1) on logout.But the C shell makes background processes immune to signalsand a HANGUP signal at logout doesn't affect the processes; they keeprunning.</P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-43404"></A>If you want the C shell to work like the Bourne shell, put lines likethese in your<SPANCLASS="link"><EMCLASS="emphasis">.logout</EM> file (<ACLASS="linkend"HREF="ch03_01.htm#UPT-ART-4800"TITLE="Running Commands When You Log Out ">3.1</A>)</SPAN>:</P><PCLASS="para"><TABLECLASS="screen.co"BORDER="1"><TR><THVALIGN="TOP"><PRECLASS="calloutlist"><ACLASS="co"HREF="ch21_02.htm"TITLE="21.2 A Better Place for Temporary Files: /tmp ">/tmp</A> <ACLASS="co"HREF="ch47_04.htm"TITLE="47.4 C Shell Variable Operators and Expressions ">! -z</A> <ACLASS="co"HREF="ch27_03.htm"TITLE="27.3 Finding Text That Doesn't Match ">-v</A> <ACLASS="co"HREF="ch08_10.htm"TITLE="8.10 eval: When You Need Another Chance ">eval</A> </PRE></TH><TDVALIGN="TOP"><PRECLASS="screen">set tf=/tmp/k$$jobs >$tfif (! -z $tf) then # there are jobs jobs >$tf.1 # rerun it to dump `Done' jobs # skip Stopped jobs (killed by default) grep -v Stopped <$tf.1 >$tf; rm $tf.1 # cannot use a pipe here if (! -z $tf) then # there are running jobs eval `echo kill -1; sed 's/.\([0-9]*\).*/%\1/' <$tf` endifendifrm $tf</PRE></TD></TR></TABLE></P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-43416"></A><ACLASS="indexterm"NAME="AUTOID-43418"></A>Warning: this may run afoul of various<SPANCLASS="link"><EMCLASS="emphasis">csh</EM> quirks (<ACLASS="linkend"HREF="ch47_02.htm"TITLE="C Shell Programming Considered Harmful ">47.2</A>)</SPAN>.[To watch this work, put<SPANCLASS="link"><CODECLASS="literal">set</CODE> <CODECLASS="literal">verbose</CODE> <CODECLASS="literal">echo</CODE> (<ACLASS="linkend"HREF="ch08_17.htm"TITLE="verbose and echo Variables Show Quoting ">8.17</A>)</SPAN>at the top of your <EMCLASS="emphasis">.logout</EM> file.If the logout process clears your screen or closes the window, you cangive yourself <CODECLASS="replaceable"><I>n</I></CODE> seconds to read the debugging output by adding<SPANCLASS="link"><CODECLASS="literal">sleep</CODE> <CODECLASS="replaceable"><I>n</I></CODE> (<ACLASS="linkend"HREF="ch40_02.htm"TITLE="Waiting a Little While: sleep ">40.2</A>)</SPAN>to the end of your <EMCLASS="emphasis">.logout</EM> file. <EMCLASS="emphasis">-JP</EM> ]The important trick is to run <CODECLASS="literal">jobs >file</CODE>, not<CODECLASS="literal">jobs | command</CODE>, as the latter runs <EMCLASS="emphasis">jobs</EM> in a<SPANCLASS="link">subshell (<ACLASS="linkend"HREF="ch38_04.htm"TITLE="Subshells ">38.4</A>)</SPAN>andthus produces no output,although <CODECLASS="literal">jobs</CODE> <CODECLASS="literal">|</CODE> <CODECLASS="replaceable"><I>any-csh-builtin</I></CODE> isgood for a laugh <CODECLASS="literal">:-)</CODE>.</P><DIVCLASS="sect1info"><PCLASS="SECT1INFO">- <SPANCLASS="authorinitials">CT</SPAN> <SPANCLASS="bibliomisc">in <ACLASS="systemitem.newsgroup"HREF="news:comp.unix.questions">comp.unix.questions</A> on Usenet, 5 August 1989</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="ch38_16.htm"TITLE="38.16 Why You Can't Kill a Zombie "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 38.16 Why You Can't Kill a Zombie "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="ch38_18.htm"TITLE="38.18 nohup "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 38.18 nohup "BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172">38.16 Why You Can't Kill a Zombie </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">38.18 nohup </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
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -