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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 51] 51.6 Cleaning script Files </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="1998-08-04T21:57:22Z"><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="ch51_01.htm"TITLE="51. Miscellaneous Useful Programs and Curiosities"><LINKREL="prev"HREF="ch51_05.htm"TITLE="51.5 Copy What You Do with script "><LINKREL="next"HREF="ch51_07.htm"TITLE="51.7 When You Get Impatient "></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="ch51_05.htm"TITLE="51.5 Copy What You Do with script "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 51.5 Copy What You Do with script "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 51<BR>Miscellaneous Useful Programs and Curiosities</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch51_07.htm"TITLE="51.7 When You Get Impatient "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 51.7 When You Get Impatient "BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-4140">51.6 Cleaning script Files </A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-60171"></A><ACLASS="indexterm"NAME="AUTOID-60173"></A><ACLASS="indexterm"NAME="AUTOID-60176"></A>As article<ACLASS="xref"HREF="ch51_05.htm"TITLE="Copy What You Do with script ">51.5</A>explains, the files made by the <EMCLASS="emphasis">script</EM> program can have straycontrol characters in them.The shell script called <EMCLASS="emphasis">script.tidy</EM> can clean them up.Dan Bernstein wrote it and posted it to Usenet; I made a few changes.It reads from files or standard input; it writes to standard output.</P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-60183"></A><ACLASS="indexterm"NAME="AUTOID-60186"></A><ACLASS="indexterm"NAME="AUTOID-60189"></A><ACLASS="indexterm"NAME="AUTOID-60192"></A><ACLASS="indexterm"NAME="AUTOID-60195"></A><ACLASS="indexterm"NAME="AUTOID-60198"></A><ACLASS="indexterm"NAME="AUTOID-60201"></A><ACLASS="indexterm"NAME="AUTOID-60204"></A><EMCLASS="emphasis">script.tidy</EM> uses the<SPANCLASS="link"><EMCLASS="emphasis">sed</EM> (<ACLASS="linkend"HREF="ch34_24.htm"TITLE="Quick Reference: sed ">34.24</A>)</SPAN>substitute command to remove CTRL-m (RETURN) characters fromthe ends of lines.It uses the <EMCLASS="emphasis">sed</EM><SPANCLASS="link">test command (<ACLASS="linkend"HREF="ch34_20.htm"TITLE="The sed Test Command ">34.20</A>)</SPAN>to repeat a series of commands that delete a character followed byCTRL-h (BACKSPACE).If you use DELETE as your<SPANCLASS="link">erase character (<ACLASS="linkend"HREF="ch05_09.htm"TITLE="Setting Your Erase, Kill, and Interrupt Characters ">5.9</A>)</SPAN>,change the script to eat DELETE instead of BACKSPACE.<EMCLASS="emphasis">script.tidy</EM> uses a<SPANCLASS="link">trick (<ACLASS="linkend"HREF="ch45_35.htm"TITLE="Using a Control Character in a Script ">45.35</A>)</SPAN>with <EMCLASS="emphasis">echo</EM> and <EMCLASS="emphasis">tr</EM> to store the control characters in shellvariables.Because the <EMCLASS="emphasis">sed</EM> script has<SPANCLASS="link">doublequotes (<ACLASS="linkend"HREF="ch08_14.htm"TITLE="Bourne Shell Quoting ">8.14</A>)</SPAN>around it, the shell variables are substituted in the right placesbefore the shell starts <EMCLASS="emphasis">sed</EM>.</P><PCLASS="para"><TABLECLASS="screen.co"BORDER="1"><TR><THVALIGN="TOP"><PRECLASS="calloutlist"> <ACLASS="co"HREF="ch08_10.htm"TITLE="8.10 eval: When You Need Another Chance ">eval</A> <ACLASS="co"HREF="ch45_07.htm"TITLE="45.7 The exec Command ">exec</A> </PRE></TH><TDVALIGN="TOP"><PRECLASS="screen"> #!/bin/sh# Public domain.# Put CTRL-M in $m and CTRL-H in $b.# Change \010 to \177 if you use DEL for erasing.eval `echo m=M b=H | tr 'MH' '\015\010'`exec sed "s/$m\$//:xs/[^$b]$b//t x" $*</PRE></TD></TR></TABLE></P><PCLASS="para">You can also hack the <EMCLASS="emphasis">sed</EM> script in <EMCLASS="emphasis">script.tidy</EM> to deletesome of your terminal's<SPANCLASS="link">escape sequences (<ACLASS="linkend"HREF="ch05_08.htm"TITLE="Terminal Escape Sequences ">5.8</A>)</SPAN>;article<ACLASS="xref"HREF="ch41_11.htm"TITLE="How termcap and terminfo Describe Terminals ">41.11</A>explains how to find these sequences.(A really automated <EMCLASS="emphasis">script.tidy</EM> would read your <EMCLASS="emphasis">termcap</EM> or<EMCLASS="emphasis">terminfo</EM> entry and look for all those escape sequences in thescript file.) </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="ch51_05.htm"TITLE="51.5 Copy What You Do with script "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 51.5 Copy What You Do with script "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="ch51_07.htm"TITLE="51.7 When You Get Impatient "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 51.7 When You Get Impatient "BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172">51.5 Copy What You Do with script </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">51.7 When You Get Impatient </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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