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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 7] 7.3 C Shell Prompt Causes Problems in vi, rsh, etc. </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="1998-08-04T21:33:43Z"><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="ch07_01.htm"TITLE="7. Setting Your Shell Prompt"><LINKREL="prev"HREF="ch07_02.htm"TITLE="7.2 Basics of Setting the Prompt "><LINKREL="next"HREF="ch07_04.htm"TITLE="7.4 Faster Prompt Setting with Built-Ins "></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="ch07_02.htm"TITLE="7.2 Basics of Setting the Prompt "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 7.2 Basics of Setting the Prompt "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 7<BR>Setting Your Shell Prompt</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch07_04.htm"TITLE="7.4 Faster Prompt Setting with Built-Ins "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 7.4 Faster Prompt Setting with Built-Ins "BORDER="0"></A></TD></TR></TABLE>&nbsp;<HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-0241">7.3 C Shell Prompt Causes Problems in vi, rsh, etc. </A></H2><PCLASS="para">[Stray prompts can cause trouble formany commands that start a noninteractive shell.This problem may have been fixed in your C shell. The point Chrismakes about speeding up your <ICLASS="filename">.cshrc</I> still applies, though. -JP]</P><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-6659"></A><ACLASS="indexterm"NAME="AUTOID-6662"></A>If you <EMCLASS="emphasis">set&nbsp;prompt</EM> in your<EMCLASS="emphasis">.cshrc</EM> filewithout carefully checking first whether or not<SPANCLASS="link"><EMCLASS="emphasis">prompt</EM> was already set (<ACLASS="linkend"HREF="ch02_09.htm"TITLE="Speeding Up Your C Shell with set prompt Test ">2.9</A>)</SPAN>,many versions of the C shell will cheerfullyprint prompts into the pipe <EMCLASS="emphasis">vi</EM> uses to expand glob characters[<SPANCLASS="link">filename wildcards (<CODECLASS="literal">*</CODE>, <CODECLASS="literal">?</CODE>, <CODECLASS="literal">[]</CODE>) (<ACLASS="linkend"HREF="ch01_16.htm"TITLE="Wildcards ">1.16</A>)</SPAN>and the<SPANCLASS="link">tilde (<CODECLASS="literal">~</CODE>) (<ACLASS="linkend"HREF="ch14_11.htm"TITLE="Finding (Anyone's) Home Directory, Quickly ">14.11</A>)</SPAN><EMCLASS="emphasis">-JP</EM>&nbsp;].</P><PCLASS="para">When you type <CODECLASS="literal">:r&nbsp;abc*</CODE>, <EMCLASS="emphasis">vi</EM> opens a pipe to the C shelland writes the command <CODECLASS="literal">echo&nbsp;abc*</CODE> down the pipe, then readsthe response.  If the response contains spaces or newlines, <EMCLASS="emphasis">vi</EM>gets confused. If you set your prompt to <CODECLASS="literal">(</CODE><CODECLASS="replaceable"><I>n</I></CODE><CODECLASS="literal">)</CODE> in your<EMCLASS="emphasis">.cshrc</EM> [i.e., if you show the history number in parentheses asthe prompt<EMCLASS="emphasis">-TOR</EM>&nbsp;], <EMCLASS="emphasis">vi</EM> tends to get:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">(1) abc.file (2)</PRE></BLOCKQUOTE></P><PCLASS="para">back from the C shell, instead of just <CODECLASS="literal">abc.file</CODE>.</P><PCLASS="para">The solution is to<SPANCLASS="link">kludge your <EMCLASS="emphasis">.cshrc</EM> (<ACLASS="linkend"HREF="ch02_09.htm"TITLE="Speeding Up Your C Shell with set prompt Test ">2.9</A>)</SPAN>like this:</P><PCLASS="para"><TABLECLASS="screen.co"BORDER="1"><TR><THVALIGN="TOP"><PRECLASS="calloutlist"><ACLASS="co"HREF="ch47_03.htm"TITLE="47.3 Conditional Statements with if ">if</A> <ACLASS="co"HREF="ch47_04.htm"TITLE="47.4 C Shell Variable Operators and Expressions ">$?prompt</A> &#13;</PRE></TH><TDVALIGN="TOP"><PRECLASS="screen">if ($?prompt) then    # things to do for an interactive shell, like:    set prompt='(\!) 'endif</PRE></TD></TR></TABLE></P><PCLASS="para">This works because a noninteractive shell has no initial prompt,while an interactive shell has it set to <CODECLASS="literal">% </CODE>.</P><PCLASS="para">If you have a large <EMCLASS="emphasis">.cshrc</EM>, this can speed things up quite a bitwhen programs run other programs with <CODECLASS="literal">csh</CODE>&nbsp;<CODECLASS="literal">-c</CODE>&nbsp;<CODECLASS="literal">'</CODE><CODECLASS="replaceable"><I>command</I></CODE><CODECLASS="literal">'</CODE>, if youput all of it inside that test.</P><DIVCLASS="sect1info"><PCLASS="SECT1INFO">- <SPANCLASS="authorinitials">CT</SPAN> <SPANCLASS="bibliomisc">in <CITECLASS="citetitle"><ACLASS="systemitem.newsgroup"HREF="news:net.unix-wizards">net.unix-wizards</A> on Usenet</CITE>, 22 April 1984</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="ch07_02.htm"TITLE="7.2 Basics of Setting the Prompt "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 7.2 Basics of Setting the Prompt "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="ch07_04.htm"TITLE="7.4 Faster Prompt Setting with Built-Ins "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 7.4 Faster Prompt Setting with Built-Ins "BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172">7.2 Basics of Setting the Prompt </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">7.4 Faster Prompt Setting with Built-Ins </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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