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<HTML><!--Distributed by F --><HEAD><TITLE>[Chapter 35] 35.22 Straightening Jagged Columns </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="1998-08-04T21:48:30Z"><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="ch35_01.htm"TITLE="35. You Can't Quite Call This Editing"><LINKREL="prev"HREF="ch35_21.htm"TITLE="35.21 Using IFS to Split Strings "><LINKREL="next"HREF="ch35_23.htm"TITLE="35.23 Rotating Text "></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="ch35_21.htm"TITLE="35.21 Using IFS to Split Strings "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 35.21 Using IFS to Split Strings "BORDER="0"></A></TD><TDALIGN="CENTER"VALIGN="TOP"WIDTH="171"><B><FONTFACE="ARIEL,HELVETICA,HELV,SANSERIF"SIZE="-1">Chapter 35<BR>You Can't Quite Call This Editing</FONT></B></TD><TDALIGN="RIGHT"VALIGN="TOP"WIDTH="172"><ACLASS="SECT1"HREF="ch35_23.htm"TITLE="35.23 Rotating Text "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 35.23 Rotating Text "BORDER="0"></A></TD></TR></TABLE> <HRALIGN="LEFT"WIDTH="515"TITLE="footer"></DIV><DIVCLASS="SECT1"><H2CLASS="sect1"><ACLASS="title"NAME="UPT-ART-7904">35.22 Straightening Jagged Columns </A></H2><PCLASS="para"><ACLASS="indexterm"NAME="AUTOID-41340"></A><ACLASS="indexterm"NAME="AUTOID-41343"></A>As we were writing this book, I decided to make a list of all thearticles, the numbers of lines and characters in each - then combinethat with the description, a status code, and the article's title.After a few minutes with<SPANCLASS="link"><EMCLASS="emphasis">wc -l -c</EM> (<ACLASS="linkend"HREF="ch29_06.htm"TITLE="Counting Lines, Words, and Characters: wc ">29.6</A>)</SPAN>,<SPANCLASS="link"><EMCLASS="emphasis">cut</EM> (<ACLASS="linkend"HREF="ch35_14.htm"TITLE="Cutting Columns or Fields with cut ">35.14</A>)</SPAN>,<SPANCLASS="link"><EMCLASS="emphasis">sort</EM> (<ACLASS="linkend"HREF="ch36_01.htm#UPT-ART-7640"TITLE="Putting Things in Order ">36.1</A>)</SPAN>,and<SPANCLASS="link"><EMCLASS="emphasis">join</EM> (<ACLASS="linkend"HREF="ch35_19.htm"TITLE="Joining Lines with join ">35.19</A>)</SPAN>,I had a file that looked like this:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>cat messfile</B></CODE>2850 2095 51441 ~BB A sed tutorial3120 868 21259 +BB mail - lots of basics6480 732 31034 + How to find sources - JIK's periodic posting <ICLASS="lineannotation">...900 lines...</I>5630 14 453 +JP Running Commands on Directory Stacks1600 12 420 !JP With find, Don't Forget -print0495 9 399 + Make 'xargs -i' use more than one filename</PRE></BLOCKQUOTE></P><PCLASS="para"> Yuck. It was tough to read. The columns needed to be straightened.A little<SPANCLASS="link"><EMCLASS="emphasis">awk</EM> (<ACLASS="linkend"HREF="ch33_11.htm"TITLE="Quick Reference: awk ">33.11</A>)</SPAN>scriptturned the mess into this:<ACLASS="indexterm"NAME="AUTOID-41361"></A></P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>cat cleanfile</B></CODE>2850 2095 51441 ~BB A sed tutorial3120 868 21259 +BB mail - lots of basics6480 732 31034 + How to find sources - JIK's periodic posting <ICLASS="lineannotation">...900 lines...</I>5630 14 453 +JP Running Commands on Directory Stacks1600 12 420 !JP With find, Don't Forget -print0495 9 399 + Make 'xargs -i' use more than one filename</PRE></BLOCKQUOTE></P><PCLASS="para">Here's the simple script I used and the command I typed to run it:</P><PCLASS="para"><BLOCKQUOTECLASS="screen"><PRECLASS="screen">% <CODECLASS="userinput"><B>cat neatcols</B></CODE>{printf "%4s %4s %6s %-4s %s\n", \ $1, $2, $3, $4, substr($0, index($0,$5))}% <CODECLASS="userinput"><B>awk -f neatcols messfile > cleanfile</B></CODE></PRE></BLOCKQUOTE></P><PCLASS="para">You can adapt that script for whatever kinds of columns you need toclean up.In case you don't know <EMCLASS="emphasis">awk</EM>, here's a quick summary:</P><ULCLASS="itemizedlist"><LICLASS="listitem"><PCLASS="para">The first line of the <EMCLASS="emphasis">printf</EM>, between double quotes (<CODECLASS="literal">"</CODE>),tells the field widths and alignments.For example, the first column should be right-aligned in 4 characters(<CODECLASS="literal">%4s</CODE>).The fourth column should be 4 characters wide left-adjusted (<CODECLASS="literal">%-4s</CODE>).The fifth column is big enough to just fit (<CODECLASS="literal">%s</CODE>).I used string (<CODECLASS="literal">%s</CODE>) instead of decimal (<CODECLASS="literal">%d</CODE>) so <EMCLASS="emphasis">awk</EM>wouldn't strip off the leading zeros in the columns. </P></LI><LICLASS="listitem"><PCLASS="para">The second line arranges the input data fields onto the output line.Here, input and output are in the same order, but I could have reordered them.The first four columns get the first four fields (<CODECLASS="literal">$1, $2, $3, $4</CODE>).</P><PCLASS="para">The fifth column is a catch-all; it gets everything else.<CODECLASS="literal">substr($0, index($0,$5))</CODE>means "find the fifth input column; print it and everything after it."</P></LI></UL><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="ch35_21.htm"TITLE="35.21 Using IFS to Split Strings "><IMGSRC="gifs/txtpreva.gif"SRC="gifs/txtpreva.gif"ALT="Previous: 35.21 Using IFS to Split Strings "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="ch35_23.htm"TITLE="35.23 Rotating Text "><IMGSRC="gifs/txtnexta.gif"SRC="gifs/txtnexta.gif"ALT="Next: 35.23 Rotating Text "BORDER="0"></A></TD></TR><TR><TDALIGN="LEFT"VALIGN="TOP"WIDTH="172">35.21 Using IFS to Split Strings </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">35.23 Rotating Text </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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