index.html

this is a book on pearl , simple example with explanation is given here. it could be beneficial for

shmwrite (ID, BUFFER, POS, SIZE)</A>

<LI><A HREF="ch25.htm#shutdownSOCKETHOW">

shutdown (SOCKET, HOW)</A>

<LI><A HREF="ch25.htm#sinEXPR">

sin ([EXPR])</A>

<LI><A HREF="ch25.htm#sleepNUMSECONDSTOSLEEP">

sleep ([NUM_SECONDS_TO_SLEEP])</A>

<LI><A HREF="ch25.htm#socketSOCKETDOMAINTYPEPROTOCOL">

socket (SOCKET, DOMAIN, TYPE, PROTOCOL)</A>

<LI><A HREF="ch25.htm#socketpairSOCKETSOCKETDOMAINTYPEPROTOCOL">

socketpair (SOCKET1, SOCKET2, DOMAIN, TYPE, PROTOCOL)</A>

<LI><A HREF="ch25.htm#sortSUBNAMEBLOCKLIST">

sort ([SUBNAME | BLOCK], LIST)</A>

<LI><A HREF="ch25.htm#spliceARRAYOFFSETLENGTHLIST">

splice (ARRAY, OFFSET, [LENGTH], [LIST])</A>

<LI><A HREF="ch25.htm#splitPATTERNEXPRLIMIT">

split ([/PATTERN/], [EXPR], [LIMIT])</A>

<LI><A HREF="ch25.htm#sprintfFORMATLIST">

sprintf (FORMAT, LIST)</A>

<LI><A HREF="ch25.htm#sqrtEXPR">

sqrt ([EXPR])</A>

<LI><A HREF="ch25.htm#srandEXPR">

srand ([EXPR])</A>

<LI><A HREF="ch25.htm#statFILEHANDLEEXPR">

stat (FILEHANDLE | EXPR)</A>

<LI><A HREF="ch25.htm#studySCALAR">

study ([SCALAR])</A>

<LI><A HREF="ch25.htm#substrEXPROFFSETLEN">

substr (EXPR, OFFSET, [LEN])</A>

<LI><A HREF="ch25.htm#symlinkOLDFILENEWFILE">

symlink (OLDFILE, NEWFILE)</A>

<LI><A HREF="ch25.htm#syscallLIST">

syscall (LIST)</A>

<LI><A HREF="ch25.htm#sysopenFILEHANDLEFILENAMEMODEPERMISSIONS">

sysopen (FILEHANDLE, FILENAME, MODE, [PERMISSIONS])</A>

<LI><A HREF="ch25.htm#sysreadFILEHANDLEBUFFERLENGTHOFFSET">

sysread (FILEHANDLE, BUFFER, LENGTH, [OFFSET])</A>

<LI><A HREF="ch25.htm#systemLIST">

system (LIST)</A>

<LI><A HREF="ch25.htm#syswriteFILEHANDLEBUFFERLENGTHOFFSET">

syswrite (FILEHANDLE, BUFFER, LENGTH, [OFFSET])</A>

<LI><A HREF="ch25.htm#tellFILEHANDLE">

tell ([FILEHANDLE])</A>

<LI><A HREF="ch25.htm#telldirDIRHANDLE">

telldir (DIRHANDLE)</A>

<LI><A HREF="ch25.htm#tieVARIABLEPACKAGENAMELIST">

tie (VARIABLE, PACKAGENAME, LIST)</A>

<LI><A HREF="ch25.htm#tiedVARIABLE">

tied (VARIABLE)</A>

<LI><A HREF="ch25.htm#time">

time ( )</A>

<LI><A HREF="ch25.htm#times">

times ( )</A>

<LI><A HREF="ch25.htm#truNCateFILEHANDLEEXPRLENGTH">

truNCate (FILEHANDLE | EXPR, LENGTH)</A>

<LI><A HREF="ch25.htm#ucEXPR">

uc (EXPR)</A>

<LI><A HREF="ch25.htm#ucfirstEXPR">

ucfirst (EXPR)</A>

<LI><A HREF="ch25.htm#umaskEXPR">

umask ([EXPR])</A>

<LI><A HREF="ch25.htm#undefEXPR">

undef ([EXPR])</A>

<LI><A HREF="ch25.htm#unlinkLIST">

unlink (LIST)</A>

<LI><A HREF="ch25.htm#unpackTEMPLATEEXPR">

unpack (TEMPLATE, EXPR)</A>

<LI><A HREF="ch25.htm#unshiftARRAYLIST">

unshift (ARRAY, LIST)</A>

<LI><A HREF="ch25.htm#untieVARIABLE">

untie (VARIABLE)</A>

<LI><A HREF="ch25.htm#utimeAccESSTIMEMODIFICATIONTIMELIST">

utime (AccESS_TIME, MODIFICATION_TIME, LIST)</A>

<LI><A HREF="ch25.htm#valuesHASH">

values (HASH)</A>

<LI><A HREF="ch25.htm#vecEXPROFFSETNUMBITS">

vec (EXPR, OFFSET, NUM_BITS)</A>

<LI><A HREF="ch25.htm#wait">

wait ( )</A>

<LI><A HREF="ch25.htm#waitpidPIDFLAGS">

waitpid (PID, FLAGS)</A>

<LI><A HREF="ch25.htm#wantarray">

wantarray ( )</A>

<LI><A HREF="ch25.htm#warnLIST">

warn ([LIST])</A>

<LI><A HREF="ch25.htm#writeFILEHANDLEEXPR">

write ([FILEHANDLE | EXPR])</A>

</UL>

</UL>



<H2><I><FONT SIZE=5 COLOR=#FF0000>Appendix </FONT></I><FONT SIZE=5 COLOR=#FF0000>D

</FONT><FONT SIZE=5>&nbsp;&nbsp;Using the Registry</FONT></H2>

<UL>

<LI><A HREF="ch26.htm#RegistryFiles">

Registry Files</A>

<UL>

<LI><A HREF="ch26.htm#HowtoBackUptheRegistry">

How to Back Up the Registry</A>

<LI><A HREF="ch26.htm#HowtoRestoretheRegistry">

How to Restore the Registry</A>

</UL>

<LI><A HREF="ch26.htm#UsingtheRegistry">

Using the Registry</A>

<UL>

<LI><A HREF="ch26.htm#OpeninganExistingKey">

Opening an Existing Key</A>

<LI><A HREF="ch26.htm#CreatingaNewKey">

Creating a New Key</A>

<LI><A HREF="ch26.htm#FindingaKeysValue">

Finding a Key's Value</A>

<LI><A HREF="ch26.htm#SettingaKeysNameValuePairs">

Setting a Key's Name-Value Pairs</A>

<LI><A HREF="ch26.htm#GettingaListofSubkeys">

Getting a List of Subkeys</A>

<LI><A HREF="ch26.htm#GettingaListofNameValuePairs">

Getting a List of Name-Value Pairs</A>

</UL>

<LI><A HREF="ch26.htm#SomeCommonUsesfortheRegistry">

Some Common Uses for the Registry</A>

<UL>

<LI><A HREF="ch26.htm#CreatingaFileAssociation">

Creating a File Association</A>

<LI><A HREF="ch26.htm#SettingtheIconforaFileExtension">

Setting the Icon for a File Extension</A>

<LI><A HREF="ch26.htm#EnablingthenewContextMenuOption">

Enabling the 'new' Context Menu Option</A>

</UL>

<LI><A HREF="ch26.htm#Summary">

Summary</A>

</UL>



<P>

<BR>

<H2><I><FONT COLOR="#FF0000"><A HREF="#CREDITS"><B>Credits</A></I></B></FONT></H2>



<HR WIDTH=100%>

<P>

<P>

Copyright&copy; 1996 by Que Corporation.

<P>

All rights reserved. Printed in the United States of America.

No part of this book may be used or reproduced in any form or

by any means, or stored in a database or retrieval system, without

prior written permission of the publisher except in the case of

brief quotations embodied in critical articles and reviews. Making

copies of any part of this book for any purpose other than your

own personal use is a violation of United States copyright laws.

For information, address Que Corporation, 201 W. 103rd Street,

Indianapolis, IN  46290. You may reach Que's direct sales line

by calling 1-800-428-5331.

<P>

<B>ISBN: 0-7897-0866-3</B>

<BR>

<A NAME="CREDITS"></A><B>HTML conversion by </B> : 

<BR>&nbsp;&nbsp;&nbsp;&nbsp;M/s. LeafWriters (India) Pvt. Ltd. <BR>

&nbsp;&nbsp;&nbsp;&nbsp;<I>Website</I> : <A HREF=http://leaf.stpn.soft.net>http://leaf.stpn.soft.net</A> 

<BR>

&nbsp;&nbsp;&nbsp;&nbsp;<I>e-mail</I> : <A HREF=mailto:[e-mail]>

[e-mail]</A>

<P>

<HR>

<CENTER>

<TABLE WIDTH=40%>

<TR><TD WIDTH=145><B><FONT SIZE=2>President</FONT></B></TD><TD WIDTH=138><I><FONT SIZE=2>Roland Elgey</FONT></I>

</TD></TR>

<TR><TD WIDTH=145><B><FONT SIZE=2>Publisher</FONT></B></TD><TD WIDTH=138><I><FONT SIZE=2>Joseph B. Wikert</FONT></I>

</TD></TR>

<TR><TD WIDTH=145><B><FONT SIZE=2>Director of Marketing</FONT></B>

</TD><TD WIDTH=138><I><FONT SIZE=2>Lynn E. Zingraf</FONT></I>

</TD></TR>

</TABLE>

<P>



<TABLE>

<TR><TD WIDTH=148><B><FONT SIZE=2>Editorial Services Director</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Elizabeth Keaffaber</FONT></I>

</TD><TD WIDTH=148><B><FONT SIZE=2>Managing Editor</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Sandy Doell</FONT></I></TD>

</TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Title Manager</FONT></B></TD>

<TD WIDTH=148><I><FONT SIZE=2>Bryan Gambrel</FONT></I></TD><TD WIDTH=148><B><FONT SIZE=2>Project Director</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Al Valvano</FONT></I></TD>

</TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Production Editors</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Susan Ross Moore, Matthew B. Cox</FONT></I>

</TD><TD WIDTH=148><B><FONT SIZE=2>Editors</FONT></B></TD><TD WIDTH=148><I><FONT SIZE=2>Elizabeth Barrett, Anne Owen, Jeff Riley</FONT></I>

</TD></TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Product Marketing Manager</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Kim Margolius</FONT></I></TD>

<TD WIDTH=148><B><FONT SIZE=2>Assistant Product Marketing Manager</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Christy M. Miller</FONT></I>

</TD></TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Technical Editors</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Joe Milton, J. David Shinn, CNE, Synergetic Resource Corp.</FONT></I>

</TD><TD WIDTH=148><B><FONT SIZE=2>Technical Specialist</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Nadeem Muhammed</FONT></I>

</TD></TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Acquisitions Coordinator</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Carmen Krikorian</FONT></I>

</TD><TD WIDTH=148><B><FONT SIZE=2>Operations Coordinator</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Patricia J. Brooks</FONT></I>

</TD></TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Editorial Assistant</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Andrea Duvall</FONT></I></TD>

<TD WIDTH=148><B><FONT SIZE=2>Book Designer</FONT></B></TD><TD WIDTH=148><I><FONT SIZE=2>Barb Kordesh</FONT></I>

</TD></TR>

<TR><TD WIDTH=148><B><FONT SIZE=2>Cover Designer</FONT></B></TD>

<TD WIDTH=148><I><FONT SIZE=2>Ruth Harvey</FONT></I></TD><TD WIDTH=148><B><FONT SIZE=2>Production</FONT></B>

</TD><TD WIDTH=148><I><FONT SIZE=2>Bryan Flores</FONT></I></TD>

</TR>

</TABLE>

</CENTER>

<HR>

<P>

<H3>About the Author</H3>

<P>

<B>David Medinets</B> has been programming siNCe 1980, when he

started with a TRS-80 Model 1. He still fondly remembers the days

when he could crosswire the keyboard to create funny-looking characters

on the display.  SiNCe those days, he has spent time debugging

Emacs on UNIX machines, working on VAXen, and messing around with

DOS microcomputers. David is married to Kathryn and lives in northwest

New Jersey. He runs Eclectic Consulting and has coauthored<I>

Special Edition Using Lotus Notes Release 4 (</I>Que<I>), Special

Edition Using Turbo C++ 4.5 for Windows (</I>Que<I>), Microsoft

Office 95 Unleashed (</I>Sams<I>), </I>and<I> Visual Basic Unleashed

</I>(Sams), among others<I>. </I>David can be reached at <B>[e-mail]</B>.

<H3>Acknowledgments</H3>

<P>

I'd like to thank all of the people at Que for making this book

possible. You'll find their names listed on the Credits page,

 so I won't list them all here. Susan Ross Moore deserves special

thanks for figuratively watching over my shoulder as I worked.

Her comments definitely made this a better book. Al Valvano was

instrumental in making sure that everything came together at the

proper time.

<P>

My wonderful wife deserves some thanks for letting me hang out

on the Internet at all hours of the day and night while I did

research for this book.

<P>

While writing this book, I have gleaned information from many

books, articles, and Web resources. Where a particular item greatly

influeNCed my thinking, I have given credit in the appropriate

section.

<P>

Dale Bewley helped to create Chapter 19, &quot;What Is CGI?&quot;-Thanks

Dale!

<P>

And of course, no Perl author should forget to thank: Larry Wall

for creating Perl in the first place; Tom Christiansen for his

remarkable contributions to the Perl community; and Randal Schwartz

for his Learning Perl book which every Perl programmer seems to

have read.

<P>

Thanks,<BR>

<I><B>David</B></I>

<H4>We'd Like to Hear from You!</H4>

<P>

As part of our continuing effort to produce books of the highest

possible quality, Que would like to hear your comments. To stay

competitive, we <I>really</I> want you, as a computer book reader

and user, to let us know what you like or dislike most about this

book or other Que products.

<P>

You can mail comments, ideas, or suggestions for improving future

editions to the address below, or send us a fax at [phone].

Our staff and authors are available for questions and comments

through our Internet site, at http://www.mcp.com/que, and<B> </B>Macmillan

Computer Publishing also has a forum on CompuServe (type <B>GO

QUEBOOKS</B> at any prompt).

<P>

In addition to exploring our forum, please feel free to contact

me personally to discuss your opinions of this book: I'm<B> </B>[e-mail]

on the Internet, and 74671,3710<B> </B>on CompuServe.

<P>

Thanks in advaNCe-your comments will help us to continue publishing

the best books available on new computer technologies in today's

market.

<P>

<DIV ALIGN=RIGHT>

<B>Al Valvano</B><br>

Project Director<BR>

Que Corporation<BR>

201 W. 103rd Street<BR>

Indianapolis, Indiana 46290<BR>

USA

</DIV>



<H3>Introduction</H3>

<P>

This book is based on the learn-by-doing priNCiple because I believe

that simply reading about a subject makes it harder to learn.

After all, you don't read about putting together a jigsaw puzzle;

you put the puzzle together yourself! Programming is the same

way. You must actually run some programs in order to really understand

the coNCepts.

<P>

<I>Perl 5 By Example</I> will teach you how to use the Perl programming

language by showing examples that demonstrate the coNCepts being

discussed. The examples are designed to give you a chaNCe to experiment-which

in turn should clarify the material.

<P>

Additional information and errata pages can be found at <B>http://www.mtolive.

com/pbe/index.html</B>.

<P>

The topics are covered in a straightforward, nontechnical manner,

which allows you to quickly understand the fundamental priNCiples.

After the main topic of each chapter is introduced, subtopics

are explored in their own sections. Each section has its own Perl

examples with explanations given in pseudocode.

<P>

Each chapter finishes with review questions of varying difficulty

based on the material in that chapter. The answers usually come

from the text or are deducible from the text, but occasionally

you might need to experiment a little. Try to answer the questions

at all difficulty levels. If you get stuck turn to the answers

provided in Appendix A. Also, look at the summary sections after

reading each chapter and return to them frequently. After you've

gone through several chapters, you'll begin to understand more

often the reason why a coNCept was illustrated or a question was

asked. Returning to questions that frustrated you earlier and

realizing that now you know the answers can be a big confideNCe

builder.

<H3>Who Should Use This Book?</H3>

<P>

<I>Perl 5 By Example</I> should be read by anyone seeking to learn

Perl. If you don't know any other programming languages, Chapters

2 through 7 will give you a solid introduction to the basics.

If you already know another language, then skip Chapters 2 through

7 to see how Perl differs from other languages and start with

Chapter 8, &quot;RefereNCes.&quot;

<P>

This book follows a simple format. Each chapter contains a single

topic-usually. First, you read about the topic and then you see

examples that let you work directly with Perl to understand how

the coNCepts can be applied to a program. At the end of each chapter

is a summary, followed by review questions and exercises.

<P>

This approach is designed to serve a broad range of readers from

novice to advaNCed. If you've never programmed before, the learn-by-doing

approach will help you move quickly and easily though this book.

If you have programming experieNCe, you'll find plenty of material

to refine and enhaNCe what you already know, and to give you a

solid understanding of how Perl works.

<H3>What Do I Need?</H3>

<P>

In order to effectively use this book you need two things. You

need a working copy of Perl 5. And you need a text editor. That's

it.

<P>

You can use the examples in this book with just about any hardware

and operating system. I'm not sure that they would work on an

Amiga system but other than that you should be able to run every

example.

<H3>How to Use This Book</H3>

<P>

There are several ways to use this book. One obvious method is

to begin at the first page and proceed in order until the last.

Most beginning programmers will use this method and the book is

specifically designed so that each chapter builds on the last.

Alternatively, you can read up to Chapter 10, &quot;Regular Expressions,&quot;

and then skip to Appendix C, &quot;FuNCtion List.&quot; You can

then read specific chapters as needed when your projects demand

them. Either approach works.<P>

<CENTER>

<TABLE BORDERCOLOR=#000000 BORDER=1 WIDTH=80%>

<TR><TD WIDTH=576><B><FONT SIZE=2>Tip</FONT></B></TD></TR>

<TR><TD WIDTH=576>

<BLOCKQUOTE>

<FONT SIZE=2>It is critical to read through the FuNCtion List (Appendix C) at least oNCe before starting any major project. Otherwise, you might spend hours developing a fuNCtion that Perl already has predefined.</FONT>

</BLOCKQUOTE>