1389 lines
22 KiB
Plaintext
1389 lines
22 KiB
Plaintext
=head1 NAME
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perlfaq - Frequently asked questions about Perl
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=head1 VERSION
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version 5.20201107
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=head1 DESCRIPTION
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The perlfaq comprises several documents that answer the most commonly
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asked questions about Perl and Perl programming. It's divided by topic
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into nine major sections outlined in this document.
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=head2 Where to find the perlfaq
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The perlfaq is an evolving document. Read the latest version at
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L<https://perldoc.perl.org/perlfaq>. It is also included in the standard Perl
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distribution.
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=head2 How to use the perlfaq
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The C<perldoc> command line tool is part of the standard Perl distribution. To
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read the perlfaq:
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$ perldoc perlfaq
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To search the perlfaq question headings:
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$ perldoc -q open
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=head2 How to contribute to the perlfaq
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Review L<https://github.com/perl-doc-cats/perlfaq/wiki>. If you don't find
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your suggestion create an issue or pull request against
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L<https://github.com/perl-doc-cats/perlfaq>.
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Once approved, changes will be distributed with the next Perl release and
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subsequently appear at L<https://perldoc.perl.org/perlfaq>.
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=head2 What if my question isn't answered in the FAQ?
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Try the resources in L<perlfaq2>.
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=head1 TABLE OF CONTENTS
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=over 4
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=item perlfaq1 - General Questions About Perl
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=item perlfaq2 - Obtaining and Learning about Perl
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=item perlfaq3 - Programming Tools
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=item perlfaq4 - Data Manipulation
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=item perlfaq5 - Files and Formats
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=item perlfaq6 - Regular Expressions
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=item perlfaq7 - General Perl Language Issues
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=item perlfaq8 - System Interaction
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=item perlfaq9 - Web, Email and Networking
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=back
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=head1 THE QUESTIONS
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=head2 L<perlfaq1>: General Questions About Perl
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This section of the FAQ answers very general, high-level questions about Perl.
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=over 4
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=item *
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What is Perl?
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=item *
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Who supports Perl? Who develops it? Why is it free?
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=item *
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Which version of Perl should I use?
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=item *
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What are Perl 4, Perl 5, or Raku (Perl 6)?
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=item *
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What is Raku (Perl 6)?
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=item *
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How stable is Perl?
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=item *
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How often are new versions of Perl released?
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=item *
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Is Perl difficult to learn?
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=item *
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How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl?
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=item *
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Can I do [task] in Perl?
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=item *
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When shouldn't I program in Perl?
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=item *
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What's the difference between "perl" and "Perl"?
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=item *
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What is a JAPH?
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=item *
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How can I convince others to use Perl?
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=back
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=head2 L<perlfaq2>: Obtaining and Learning about Perl
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This section of the FAQ answers questions about where to find source and documentation for Perl, support, and related matters.
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=over 4
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=item *
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What machines support Perl? Where do I get it?
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=item *
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How can I get a binary version of Perl?
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=item *
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I don't have a C compiler. How can I build my own Perl interpreter?
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=item *
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I copied the Perl binary from one machine to another, but scripts don't work.
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=item *
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I grabbed the sources and tried to compile but gdbm/dynamic loading/malloc/linking/... failed. How do I make it work?
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=item *
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What modules and extensions are available for Perl? What is CPAN?
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=item *
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Where can I get information on Perl?
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=item *
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What is perl.com? Perl Mongers? pm.org? perl.org? cpan.org?
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=item *
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Where can I post questions?
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=item *
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Perl Books
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=item *
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Which magazines have Perl content?
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=item *
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Which Perl blogs should I read?
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=item *
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What mailing lists are there for Perl?
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=item *
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Where can I buy a commercial version of Perl?
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=item *
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Where do I send bug reports?
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=back
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=head2 L<perlfaq3>: Programming Tools
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This section of the FAQ answers questions related to programmer tools and programming support.
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=over 4
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=item *
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How do I do (anything)?
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=item *
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How can I use Perl interactively?
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=item *
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How do I find which modules are installed on my system?
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=item *
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How do I debug my Perl programs?
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=item *
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How do I profile my Perl programs?
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=item *
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How do I cross-reference my Perl programs?
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=item *
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Is there a pretty-printer (formatter) for Perl?
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=item *
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Is there an IDE or Windows Perl Editor?
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=item *
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Where can I get Perl macros for vi?
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=item *
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Where can I get perl-mode or cperl-mode for emacs?
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=item *
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How can I use curses with Perl?
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=item *
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How can I write a GUI (X, Tk, Gtk, etc.) in Perl?
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=item *
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How can I make my Perl program run faster?
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=item *
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How can I make my Perl program take less memory?
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=item *
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Is it safe to return a reference to local or lexical data?
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=item *
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How can I free an array or hash so my program shrinks?
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=item *
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How can I make my CGI script more efficient?
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=item *
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How can I hide the source for my Perl program?
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=item *
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How can I compile my Perl program into byte code or C?
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=item *
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How can I get C<#!perl> to work on [MS-DOS,NT,...]?
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=item *
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Can I write useful Perl programs on the command line?
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=item *
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Why don't Perl one-liners work on my DOS/Mac/VMS system?
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=item *
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Where can I learn about CGI or Web programming in Perl?
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=item *
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Where can I learn about object-oriented Perl programming?
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=item *
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Where can I learn about linking C with Perl?
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=item *
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I've read perlembed, perlguts, etc., but I can't embed perl in my C program; what am I doing wrong?
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=item *
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When I tried to run my script, I got this message. What does it mean?
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=item *
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What's MakeMaker?
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=back
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=head2 L<perlfaq4>: Data Manipulation
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This section of the FAQ answers questions related to manipulating numbers, dates, strings, arrays, hashes, and miscellaneous data issues.
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=over 4
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=item *
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Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I should be getting (eg, 19.95)?
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=item *
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Why is int() broken?
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=item *
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Why isn't my octal data interpreted correctly?
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=item *
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Does Perl have a round() function? What about ceil() and floor()? Trig functions?
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=item *
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How do I convert between numeric representations/bases/radixes?
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=item *
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Why doesn't & work the way I want it to?
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=item *
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How do I multiply matrices?
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=item *
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How do I perform an operation on a series of integers?
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=item *
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How can I output Roman numerals?
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=item *
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Why aren't my random numbers random?
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=item *
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How do I get a random number between X and Y?
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=item *
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How do I find the day or week of the year?
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=item *
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How do I find the current century or millennium?
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=item *
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How can I compare two dates and find the difference?
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=item *
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How can I take a string and turn it into epoch seconds?
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=item *
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How can I find the Julian Day?
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=item *
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How do I find yesterday's date?
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=item *
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Does Perl have a Year 2000 or 2038 problem? Is Perl Y2K compliant?
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=item *
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How do I validate input?
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=item *
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How do I unescape a string?
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=item *
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How do I remove consecutive pairs of characters?
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=item *
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How do I expand function calls in a string?
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=item *
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How do I find matching/nesting anything?
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=item *
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How do I reverse a string?
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=item *
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How do I expand tabs in a string?
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=item *
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How do I reformat a paragraph?
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=item *
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How can I access or change N characters of a string?
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=item *
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How do I change the Nth occurrence of something?
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=item *
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How can I count the number of occurrences of a substring within a string?
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=item *
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How do I capitalize all the words on one line?
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=item *
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How can I split a [character]-delimited string except when inside [character]?
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=item *
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How do I strip blank space from the beginning/end of a string?
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=item *
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How do I pad a string with blanks or pad a number with zeroes?
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=item *
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How do I extract selected columns from a string?
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=item *
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How do I find the soundex value of a string?
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=item *
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How can I expand variables in text strings?
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=item *
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What's wrong with always quoting "$vars"?
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=item *
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Why don't my E<lt>E<lt>HERE documents work?
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=item *
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What is the difference between a list and an array?
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=item *
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What is the difference between $array[1] and @array[1]?
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=item *
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How can I remove duplicate elements from a list or array?
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=item *
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How can I tell whether a certain element is contained in a list or array?
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=item *
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How do I compute the difference of two arrays? How do I compute the intersection of two arrays?
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=item *
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How do I test whether two arrays or hashes are equal?
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=item *
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How do I find the first array element for which a condition is true?
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=item *
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How do I handle linked lists?
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=item *
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How do I handle circular lists?
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=item *
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How do I shuffle an array randomly?
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=item *
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How do I process/modify each element of an array?
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=item *
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How do I select a random element from an array?
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=item *
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How do I permute N elements of a list?
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=item *
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How do I sort an array by (anything)?
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=item *
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How do I manipulate arrays of bits?
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=item *
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Why does defined() return true on empty arrays and hashes?
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=item *
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How do I process an entire hash?
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=item *
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How do I merge two hashes?
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=item *
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What happens if I add or remove keys from a hash while iterating over it?
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=item *
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How do I look up a hash element by value?
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=item *
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How can I know how many entries are in a hash?
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=item *
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How do I sort a hash (optionally by value instead of key)?
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=item *
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How can I always keep my hash sorted?
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=item *
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What's the difference between "delete" and "undef" with hashes?
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=item *
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Why don't my tied hashes make the defined/exists distinction?
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=item *
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How do I reset an each() operation part-way through?
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=item *
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How can I get the unique keys from two hashes?
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=item *
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How can I store a multidimensional array in a DBM file?
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=item *
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How can I make my hash remember the order I put elements into it?
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=item *
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Why does passing a subroutine an undefined element in a hash create it?
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=item *
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How can I make the Perl equivalent of a C structure/C++ class/hash or array of hashes or arrays?
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=item *
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How can I use a reference as a hash key?
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=item *
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How can I check if a key exists in a multilevel hash?
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=item *
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How can I prevent addition of unwanted keys into a hash?
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=item *
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How do I handle binary data correctly?
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=item *
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How do I determine whether a scalar is a number/whole/integer/float?
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=item *
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How do I keep persistent data across program calls?
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=item *
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How do I print out or copy a recursive data structure?
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=item *
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How do I define methods for every class/object?
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=item *
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How do I verify a credit card checksum?
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=item *
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How do I pack arrays of doubles or floats for XS code?
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=back
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=head2 L<perlfaq5>: Files and Formats
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This section deals with I/O and the "f" issues: filehandles, flushing, formats, and footers.
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=over 4
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=item *
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How do I flush/unbuffer an output filehandle? Why must I do this?
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=item *
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How do I change, delete, or insert a line in a file, or append to the beginning of a file?
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=item *
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How do I count the number of lines in a file?
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=item *
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How do I delete the last N lines from a file?
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=item *
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How can I use Perl's C<-i> option from within a program?
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=item *
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How can I copy a file?
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=item *
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How do I make a temporary file name?
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=item *
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How can I manipulate fixed-record-length files?
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=item *
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How can I make a filehandle local to a subroutine? How do I pass filehandles between subroutines? How do I make an array of filehandles?
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=item *
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How can I use a filehandle indirectly?
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=item *
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How can I open a filehandle to a string?
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=item *
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How can I set up a footer format to be used with write()?
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=item *
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How can I write() into a string?
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=item *
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How can I output my numbers with commas added?
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=item *
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How can I translate tildes (~) in a filename?
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=item *
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How come when I open a file read-write it wipes it out?
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=item *
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Why do I sometimes get an "Argument list too long" when I use E<lt>*E<gt>?
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=item *
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How can I open a file named with a leading "E<gt>" or trailing blanks?
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=item *
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How can I reliably rename a file?
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=item *
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|
|
|
How can I lock a file?
|
|
|
|
=item *
|
|
|
|
Why can't I just open(FH, "E<gt>file.lock")?
|
|
|
|
=item *
|
|
|
|
I still don't get locking. I just want to increment the number in the file. How can I do this?
|
|
|
|
=item *
|
|
|
|
All I want to do is append a small amount of text to the end of a file. Do I still have to use locking?
|
|
|
|
=item *
|
|
|
|
How do I randomly update a binary file?
|
|
|
|
=item *
|
|
|
|
How do I get a file's timestamp in perl?
|
|
|
|
=item *
|
|
|
|
How do I set a file's timestamp in perl?
|
|
|
|
=item *
|
|
|
|
How do I print to more than one file at once?
|
|
|
|
=item *
|
|
|
|
How can I read in an entire file all at once?
|
|
|
|
=item *
|
|
|
|
How can I read in a file by paragraphs?
|
|
|
|
=item *
|
|
|
|
How can I read a single character from a file? From the keyboard?
|
|
|
|
=item *
|
|
|
|
How can I tell whether there's a character waiting on a filehandle?
|
|
|
|
=item *
|
|
|
|
How do I do a C<tail -f> in perl?
|
|
|
|
=item *
|
|
|
|
How do I dup() a filehandle in Perl?
|
|
|
|
=item *
|
|
|
|
How do I close a file descriptor by number?
|
|
|
|
=item *
|
|
|
|
Why can't I use "C:\temp\foo" in DOS paths? Why doesn't `C:\temp\foo.exe` work?
|
|
|
|
=item *
|
|
|
|
Why doesn't glob("*.*") get all the files?
|
|
|
|
=item *
|
|
|
|
Why does Perl let me delete read-only files? Why does C<-i> clobber protected files? Isn't this a bug in Perl?
|
|
|
|
=item *
|
|
|
|
How do I select a random line from a file?
|
|
|
|
=item *
|
|
|
|
Why do I get weird spaces when I print an array of lines?
|
|
|
|
=item *
|
|
|
|
How do I traverse a directory tree?
|
|
|
|
=item *
|
|
|
|
How do I delete a directory tree?
|
|
|
|
=item *
|
|
|
|
How do I copy an entire directory?
|
|
|
|
=back
|
|
|
|
|
|
=head2 L<perlfaq6>: Regular Expressions
|
|
|
|
This section is surprisingly small because the rest of the FAQ is littered with answers involving regular expressions. For example, decoding a URL and checking whether something is a number can be handled with regular expressions, but those answers are found elsewhere in this document (in perlfaq9 : "How do I decode or create those %-encodings on the web" and perlfaq4 : "How do I determine whether a scalar is a number/whole/integer/float", to be precise).
|
|
|
|
=over 4
|
|
|
|
=item *
|
|
|
|
How can I hope to use regular expressions without creating illegible and unmaintainable code?
|
|
|
|
=item *
|
|
|
|
I'm having trouble matching over more than one line. What's wrong?
|
|
|
|
=item *
|
|
|
|
How can I pull out lines between two patterns that are themselves on different lines?
|
|
|
|
=item *
|
|
|
|
How do I match XML, HTML, or other nasty, ugly things with a regex?
|
|
|
|
=item *
|
|
|
|
I put a regular expression into $/ but it didn't work. What's wrong?
|
|
|
|
=item *
|
|
|
|
How do I substitute case-insensitively on the LHS while preserving case on the RHS?
|
|
|
|
=item *
|
|
|
|
How can I make C<\w> match national character sets?
|
|
|
|
=item *
|
|
|
|
How can I match a locale-smart version of C</[a-zA-Z]/> ?
|
|
|
|
=item *
|
|
|
|
How can I quote a variable to use in a regex?
|
|
|
|
=item *
|
|
|
|
What is C</o> really for?
|
|
|
|
=item *
|
|
|
|
How do I use a regular expression to strip C-style comments from a file?
|
|
|
|
=item *
|
|
|
|
Can I use Perl regular expressions to match balanced text?
|
|
|
|
=item *
|
|
|
|
What does it mean that regexes are greedy? How can I get around it?
|
|
|
|
=item *
|
|
|
|
How do I process each word on each line?
|
|
|
|
=item *
|
|
|
|
How can I print out a word-frequency or line-frequency summary?
|
|
|
|
=item *
|
|
|
|
How can I do approximate matching?
|
|
|
|
=item *
|
|
|
|
How do I efficiently match many regular expressions at once?
|
|
|
|
=item *
|
|
|
|
Why don't word-boundary searches with C<\b> work for me?
|
|
|
|
=item *
|
|
|
|
Why does using $&, $`, or $' slow my program down?
|
|
|
|
=item *
|
|
|
|
What good is C<\G> in a regular expression?
|
|
|
|
=item *
|
|
|
|
Are Perl regexes DFAs or NFAs? Are they POSIX compliant?
|
|
|
|
=item *
|
|
|
|
What's wrong with using grep in a void context?
|
|
|
|
=item *
|
|
|
|
How can I match strings with multibyte characters?
|
|
|
|
=item *
|
|
|
|
How do I match a regular expression that's in a variable?
|
|
|
|
=back
|
|
|
|
|
|
=head2 L<perlfaq7>: General Perl Language Issues
|
|
|
|
This section deals with general Perl language issues that don't clearly fit into any of the other sections.
|
|
|
|
=over 4
|
|
|
|
=item *
|
|
|
|
Can I get a BNF/yacc/RE for the Perl language?
|
|
|
|
=item *
|
|
|
|
What are all these $@%&* punctuation signs, and how do I know when to use them?
|
|
|
|
=item *
|
|
|
|
Do I always/never have to quote my strings or use semicolons and commas?
|
|
|
|
=item *
|
|
|
|
How do I skip some return values?
|
|
|
|
=item *
|
|
|
|
How do I temporarily block warnings?
|
|
|
|
=item *
|
|
|
|
What's an extension?
|
|
|
|
=item *
|
|
|
|
Why do Perl operators have different precedence than C operators?
|
|
|
|
=item *
|
|
|
|
How do I declare/create a structure?
|
|
|
|
=item *
|
|
|
|
How do I create a module?
|
|
|
|
=item *
|
|
|
|
How do I adopt or take over a module already on CPAN?
|
|
|
|
=item *
|
|
|
|
How do I create a class?
|
|
|
|
=item *
|
|
|
|
How can I tell if a variable is tainted?
|
|
|
|
=item *
|
|
|
|
What's a closure?
|
|
|
|
=item *
|
|
|
|
What is variable suicide and how can I prevent it?
|
|
|
|
=item *
|
|
|
|
How can I pass/return a {Function, FileHandle, Array, Hash, Method, Regex}?
|
|
|
|
=item *
|
|
|
|
How do I create a static variable?
|
|
|
|
=item *
|
|
|
|
What's the difference between dynamic and lexical (static) scoping? Between local() and my()?
|
|
|
|
=item *
|
|
|
|
How can I access a dynamic variable while a similarly named lexical is in scope?
|
|
|
|
=item *
|
|
|
|
What's the difference between deep and shallow binding?
|
|
|
|
=item *
|
|
|
|
Why doesn't "my($foo) = E<lt>$fhE<gt>;" work right?
|
|
|
|
=item *
|
|
|
|
How do I redefine a builtin function, operator, or method?
|
|
|
|
=item *
|
|
|
|
What's the difference between calling a function as &foo and foo()?
|
|
|
|
=item *
|
|
|
|
How do I create a switch or case statement?
|
|
|
|
=item *
|
|
|
|
How can I catch accesses to undefined variables, functions, or methods?
|
|
|
|
=item *
|
|
|
|
Why can't a method included in this same file be found?
|
|
|
|
=item *
|
|
|
|
How can I find out my current or calling package?
|
|
|
|
=item *
|
|
|
|
How can I comment out a large block of Perl code?
|
|
|
|
=item *
|
|
|
|
How do I clear a package?
|
|
|
|
=item *
|
|
|
|
How can I use a variable as a variable name?
|
|
|
|
=item *
|
|
|
|
What does "bad interpreter" mean?
|
|
|
|
=item *
|
|
|
|
Do I need to recompile XS modules when there is a change in the C library?
|
|
|
|
=back
|
|
|
|
|
|
=head2 L<perlfaq8>: System Interaction
|
|
|
|
This section of the Perl FAQ covers questions involving operating system interaction. Topics include interprocess communication (IPC), control over the user-interface (keyboard, screen and pointing devices), and most anything else not related to data manipulation.
|
|
|
|
=over 4
|
|
|
|
=item *
|
|
|
|
How do I find out which operating system I'm running under?
|
|
|
|
=item *
|
|
|
|
How come exec() doesn't return?
|
|
|
|
=item *
|
|
|
|
How do I do fancy stuff with the keyboard/screen/mouse?
|
|
|
|
=item *
|
|
|
|
How do I print something out in color?
|
|
|
|
=item *
|
|
|
|
How do I read just one key without waiting for a return key?
|
|
|
|
=item *
|
|
|
|
How do I check whether input is ready on the keyboard?
|
|
|
|
=item *
|
|
|
|
How do I clear the screen?
|
|
|
|
=item *
|
|
|
|
How do I get the screen size?
|
|
|
|
=item *
|
|
|
|
How do I ask the user for a password?
|
|
|
|
=item *
|
|
|
|
How do I read and write the serial port?
|
|
|
|
=item *
|
|
|
|
How do I decode encrypted password files?
|
|
|
|
=item *
|
|
|
|
How do I start a process in the background?
|
|
|
|
=item *
|
|
|
|
How do I trap control characters/signals?
|
|
|
|
=item *
|
|
|
|
How do I modify the shadow password file on a Unix system?
|
|
|
|
=item *
|
|
|
|
How do I set the time and date?
|
|
|
|
=item *
|
|
|
|
How can I sleep() or alarm() for under a second?
|
|
|
|
=item *
|
|
|
|
How can I measure time under a second?
|
|
|
|
=item *
|
|
|
|
How can I do an atexit() or setjmp()/longjmp()? (Exception handling)
|
|
|
|
=item *
|
|
|
|
Why doesn't my sockets program work under System V (Solaris)? What does the error message "Protocol not supported" mean?
|
|
|
|
=item *
|
|
|
|
How can I call my system's unique C functions from Perl?
|
|
|
|
=item *
|
|
|
|
Where do I get the include files to do ioctl() or syscall()?
|
|
|
|
=item *
|
|
|
|
Why do setuid perl scripts complain about kernel problems?
|
|
|
|
=item *
|
|
|
|
How can I open a pipe both to and from a command?
|
|
|
|
=item *
|
|
|
|
Why can't I get the output of a command with system()?
|
|
|
|
=item *
|
|
|
|
How can I capture STDERR from an external command?
|
|
|
|
=item *
|
|
|
|
Why doesn't open() return an error when a pipe open fails?
|
|
|
|
=item *
|
|
|
|
What's wrong with using backticks in a void context?
|
|
|
|
=item *
|
|
|
|
How can I call backticks without shell processing?
|
|
|
|
=item *
|
|
|
|
Why can't my script read from STDIN after I gave it EOF (^D on Unix, ^Z on MS-DOS)?
|
|
|
|
=item *
|
|
|
|
How can I convert my shell script to perl?
|
|
|
|
=item *
|
|
|
|
Can I use perl to run a telnet or ftp session?
|
|
|
|
=item *
|
|
|
|
How can I write expect in Perl?
|
|
|
|
=item *
|
|
|
|
Is there a way to hide perl's command line from programs such as "ps"?
|
|
|
|
=item *
|
|
|
|
I {changed directory, modified my environment} in a perl script. How come the change disappeared when I exited the script? How do I get my changes to be visible?
|
|
|
|
=item *
|
|
|
|
How do I close a process's filehandle without waiting for it to complete?
|
|
|
|
=item *
|
|
|
|
How do I fork a daemon process?
|
|
|
|
=item *
|
|
|
|
How do I find out if I'm running interactively or not?
|
|
|
|
=item *
|
|
|
|
How do I timeout a slow event?
|
|
|
|
=item *
|
|
|
|
How do I set CPU limits?
|
|
|
|
=item *
|
|
|
|
How do I avoid zombies on a Unix system?
|
|
|
|
=item *
|
|
|
|
How do I use an SQL database?
|
|
|
|
=item *
|
|
|
|
How do I make a system() exit on control-C?
|
|
|
|
=item *
|
|
|
|
How do I open a file without blocking?
|
|
|
|
=item *
|
|
|
|
How do I tell the difference between errors from the shell and perl?
|
|
|
|
=item *
|
|
|
|
How do I install a module from CPAN?
|
|
|
|
=item *
|
|
|
|
What's the difference between require and use?
|
|
|
|
=item *
|
|
|
|
How do I keep my own module/library directory?
|
|
|
|
=item *
|
|
|
|
How do I add the directory my program lives in to the module/library search path?
|
|
|
|
=item *
|
|
|
|
How do I add a directory to my include path (@INC) at runtime?
|
|
|
|
=item *
|
|
|
|
Where are modules installed?
|
|
|
|
=item *
|
|
|
|
What is socket.ph and where do I get it?
|
|
|
|
=back
|
|
|
|
|
|
=head2 L<perlfaq9>: Web, Email and Networking
|
|
|
|
This section deals with questions related to running web sites, sending and receiving email as well as general networking.
|
|
|
|
=over 4
|
|
|
|
=item *
|
|
|
|
Should I use a web framework?
|
|
|
|
=item *
|
|
|
|
Which web framework should I use?
|
|
|
|
=item *
|
|
|
|
What is Plack and PSGI?
|
|
|
|
=item *
|
|
|
|
How do I remove HTML from a string?
|
|
|
|
=item *
|
|
|
|
How do I extract URLs?
|
|
|
|
=item *
|
|
|
|
How do I fetch an HTML file?
|
|
|
|
=item *
|
|
|
|
How do I automate an HTML form submission?
|
|
|
|
=item *
|
|
|
|
How do I decode or create those %-encodings on the web?
|
|
|
|
=item *
|
|
|
|
How do I redirect to another page?
|
|
|
|
=item *
|
|
|
|
How do I put a password on my web pages?
|
|
|
|
=item *
|
|
|
|
How do I make sure users can't enter values into a form that causes my CGI script to do bad things?
|
|
|
|
=item *
|
|
|
|
How do I parse a mail header?
|
|
|
|
=item *
|
|
|
|
How do I check a valid mail address?
|
|
|
|
=item *
|
|
|
|
How do I decode a MIME/BASE64 string?
|
|
|
|
=item *
|
|
|
|
How do I find the user's mail address?
|
|
|
|
=item *
|
|
|
|
How do I send email?
|
|
|
|
=item *
|
|
|
|
How do I use MIME to make an attachment to a mail message?
|
|
|
|
=item *
|
|
|
|
How do I read email?
|
|
|
|
=item *
|
|
|
|
How do I find out my hostname, domainname, or IP address?
|
|
|
|
=item *
|
|
|
|
How do I fetch/put an (S)FTP file?
|
|
|
|
=item *
|
|
|
|
How can I do RPC in Perl?
|
|
|
|
=back
|
|
|
|
|
|
|
|
=head1 CREDITS
|
|
|
|
Tom Christiansen wrote the original perlfaq then expanded it with the
|
|
help of Nat Torkington. brian d foy substantially edited and expanded
|
|
the perlfaq. perlfaq-workers and others have also supplied feedback,
|
|
patches and corrections over the years.
|
|
|
|
=head1 AUTHOR AND COPYRIGHT
|
|
|
|
Tom Christiansen wrote the original version of this document.
|
|
brian d foy C<< <bdfoy@cpan.org> >> wrote this version. See the
|
|
individual perlfaq documents for additional copyright information.
|
|
|
|
This document is available under the same terms as Perl itself. Code
|
|
examples in all the perlfaq documents are in the public domain. Use
|
|
them as you see fit (and at your own risk with no warranty from anyone).
|