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10 files changed, 498 insertions, 389 deletions
diff --git a/pod/perlfaq.pod b/pod/perlfaq.pod index f892238c02..7b50831f59 100644 --- a/pod/perlfaq.pod +++ b/pod/perlfaq.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq - frequently asked questions about Perl +perlfaq - frequently asked questions about Perl ($Revision: 3606 $) =head1 DESCRIPTION @@ -24,8 +24,8 @@ at http://faq.perl.org/ . The perlfaq-workers periodically post extracts of the latest perlfaq to comp.lang.perl.misc. You can view the source tree at -http://cvs.perl.org/viewcvs/cvs-public/perlfaq/ (which is outside of the -main Perl source tree). The CVS repository notes all changes to the FAQ +https://svn.perl.org/modules/perlfaq/trunk/ (which is outside of the +main Perl source tree). The SVN repository notes all changes to the FAQ and holds the latest version of the working documents and may vary significantly from the version distributed with the latest version of Perl. Check the repository before sending your corrections. diff --git a/pod/perlfaq1.pod b/pod/perlfaq1.pod index 5c10f9cd75..1078b7ee15 100644 --- a/pod/perlfaq1.pod +++ b/pod/perlfaq1.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq1 - General Questions About Perl ($Revision: 1.19 $, $Date: 2005/12/31 00:54:37 $) +perlfaq1 - General Questions About Perl ($Revision: 3606 $) =head1 DESCRIPTION @@ -58,20 +58,20 @@ users the informal support will more than suffice. See the answer to (contributed by brian d foy) -There is often a matter of opinion and taste, and there isn't any -one answer that fits anyone. In general, you want to use either -the current stable release, or the stable release immediately prior -to that one. Currently, those are perl5.8.x and perl5.6.x, respectively. +There is often a matter of opinion and taste, and there isn't any one +answer that fits anyone. In general, you want to use either the current +stable release, or the stable release immediately prior to that one. +Currently, those are perl5.8.x and perl5.6.x, respectively. -Beyond that, you have to consider several things and decide which -is best for you. +Beyond that, you have to consider several things and decide which is best +for you. =over 4 =item * -If things aren't broken, upgrading perl may break -them (or at least issue new warnings). +If things aren't broken, upgrading perl may break them (or at least issue +new warnings). =item * @@ -79,49 +79,46 @@ The latest versions of perl have more bug fixes. =item * -The Perl community is geared toward supporting the most -recent releases, so you'll have an easier time finding help for -those. +The Perl community is geared toward supporting the most recent releases, +so you'll have an easier time finding help for those. =item * -Versions prior to perl5.004 had serious security problems with -buffer overflows, and in some cases have CERT advisories (for -instance, http://www.cert.org/advisories/CA-1997-17.html ). +Versions prior to perl5.004 had serious security problems with buffer +overflows, and in some cases have CERT advisories (for instance, +http://www.cert.org/advisories/CA-1997-17.html ). =item * -The latest versions are probably the least deployed and -widely tested, so you may want to wait a few months after their -release and see what problems others have if you are risk averse. +The latest versions are probably the least deployed and widely tested, so +you may want to wait a few months after their release and see what +problems others have if you are risk averse. =item * -The immediate, previous releases (i.e. perl5.6.x ) are usually -maintained for a while, although not at the same level as the -current releases. +The immediate, previous releases (i.e. perl5.6.x ) are usually maintained +for a while, although not at the same level as the current releases. =item * -No one is actively supporting perl4.x. Five years ago it was -a dead camel carcass (according to this document). Now it's barely -a skeleton as its whitewashed bones have fractured or eroded. +No one is actively supporting perl4.x. Five years ago it was a dead +camel carcass (according to this document). Now it's barely a skeleton +as its whitewashed bones have fractured or eroded. =item * -There is no perl6.x for the next couple of years. Stay tuned, -but don't worry that you'll have to change major versions of Perl -soon (i.e. before 2006). +There is no perl6.x for the next couple of years. Stay tuned, but don't +worry that you'll have to change major versions of Perl soon (i.e. before +2008). =item * -There are really two tracks of perl development: a -maintenance version and an experimental version. The -maintenance versions are stable, and have an even number -as the minor release (i.e. perl5.8.x, where 8 is the minor -release). The experimental versions may include features that -don't make it into the stable versions, and have an odd number -as the minor release (i.e. perl5.9.x, where 9 is the minor release). +There are really two tracks of perl development: a maintenance version +and an experimental version. The maintenance versions are stable, and +have an even number as the minor release (i.e. perl5.8.x, where 8 is the +minor release). The experimental versions may include features that +don't make it into the stable versions, and have an odd number as the +minor release (i.e. perl5.9.x, where 9 is the minor release). =back @@ -155,15 +152,18 @@ See L<perlhist> for a history of Perl revisions. =head2 What is Ponie? -At The O'Reilly Open Source Software Convention in 2003, Artur -Bergman, Fotango, and The Perl Foundation announced a project to -run perl5 on the Parrot virtual machine named Ponie. Ponie stands for -Perl On New Internal Engine. The Perl 5.10 language implementation -will be used for Ponie, and there will be no language level -differences between perl5 and ponie. Ponie is not a complete rewrite -of perl5. +(contributed by brian d foy) + +Ponie stands for "Perl On the New Internal Engine", started by Arthur +Bergman from Fotango in 2003, and subsequently run as a project of The +Perl Foundation. Instead of using the current Perl internals, Ponie +creates a new one that provides a translation path from Perl 5 to Perl 6 +(or anything else that targets Parrot, actually). You can also just keep +using Perl 5 with Parrot, the virtual machine which will compile and run +Perl 6 bytecode. -For more details, see http://www.poniecode.org/ +You can get more information at http://www.poniecode.org/ and +http://www.parrotcode.org . =head2 What is perl6? @@ -328,70 +328,83 @@ programmers prefer to avoid them altogether. =head2 What is a JAPH? -These are the "just another perl hacker" signatures that some people -sign their postings with. Randal Schwartz made these famous. About -100 of the earlier ones are available from -http://www.cpan.org/misc/japh . +(contributed by brian d foy) + +JAPH stands for "Just another Perl hacker,", which Randal Schwartz used +to sign email and usenet messages starting in the late 1980s. He +previously used the phrase with many subjects ("Just another x hacker,"), +so to distinguish his JAPH, he started to write them as Perl programs: + + print "Just another Perl hacker,"; + +Note the trailing comma and space, which allows the addition of other +JAxH clauses for his many other interests. + +Other people picked up on this and started to write clever or obfuscated +programs to produce the same output, spinning things quickly out of +control while still providing hours of amusement for their creators and +readers. + +CPAN has several JAPH programs at http://www.cpan.org/misc/japh . =head2 Where can I get a list of Larry Wall witticisms? -Over a hundred quips by Larry, from postings of his or source code, -can be found at http://www.cpan.org/misc/lwall-quotes.txt.gz . - -=head2 How can I convince my sysadmin/supervisor/employees to use version 5/5.6.1/Perl instead of some other language? - -If your manager or employees are wary of unsupported software, or -software which doesn't officially ship with your operating system, you -might try to appeal to their self-interest. If programmers can be -more productive using and utilizing Perl constructs, functionality, -simplicity, and power, then the typical manager/supervisor/employee -may be persuaded. Regarding using Perl in general, it's also -sometimes helpful to point out that delivery times may be reduced -using Perl compared to other languages. - -If you have a project which has a bottleneck, especially in terms of -translation or testing, Perl almost certainly will provide a viable, -quick solution. In conjunction with any persuasion effort, you -should not fail to point out that Perl is used, quite extensively, and -with extremely reliable and valuable results, at many large computer -software and hardware companies throughout the world. In fact, -many Unix vendors now ship Perl by default. Support is usually -just a news-posting away, if you can't find the answer in the -I<comprehensive> documentation, including this FAQ. - -See http://www.perl.org/advocacy/ for more information. - -If you face reluctance to upgrading from an older version of perl, -then point out that version 4 is utterly unmaintained and unsupported -by the Perl Development Team. Another big sell for Perl5 is the large -number of modules and extensions which greatly reduce development time -for any given task. Also mention that the difference between version -4 and version 5 of Perl is like the difference between awk and C++. -(Well, OK, maybe it's not quite that distinct, but you get the idea.) -If you want support and a reasonable guarantee that what you're -developing will continue to work in the future, then you have to run -the supported version. As of December 2003 that means running either -5.8.2 (released in November 2003), or one of the older releases like -5.6.2 (also released in November 2003; a maintenance release to let perl -5.6 compile on newer systems as 5.6.1 was released in April 2001) or -5.005_03 (released in March 1999), -although 5.004_05 isn't that bad if you B<absolutely> need such an old -version (released in April 1999) for stability reasons. -Anything older than 5.004_05 shouldn't be used. - -Of particular note is the massive bug hunt for buffer overflow -problems that went into the 5.004 release. All releases prior to -that, including perl4, are considered insecure and should be upgraded -as soon as possible. - -In August 2000 in all Linux distributions a new security problem was -found in the optional 'suidperl' (not built or installed by default) -in all the Perl branches 5.6, 5.005, and 5.004, see -http://www.cpan.org/src/5.0/sperl-2000-08-05/ -Perl maintenance releases 5.6.1 and 5.8.0 have this security hole closed. -Most, if not all, Linux distribution have patches for this -vulnerability available, see http://www.linuxsecurity.com/advisories/ , -but the most recommendable way is to upgrade to at least Perl 5.6.1. +(contributed by brian d foy) + +Google "larry wall quotes"! You might even try the "I feel lucky" button. +:) + +Wikiquote has the witticisms from Larry along with their source, +including his usenet postings and source code comments. + +If you want a plain text file, try +http://www.cpan.org/misc/lwall-quotes.txt.gz . + +=head2 How can I convince others to use Perl? + +(contributed by brian d foy) + +Appeal to their self interest! If Perl is new (and thus scary) to them, +find something that Perl can do to solve one of their problems. That +might mean that Perl either saves them something (time, headaches, money) +or gives them something (flexibility, power, testability). + +In general, the benefit of a language is closely related to the skill of +the people using that language. If you or your team can be more faster, +better, and stronger through Perl, you'll deliver more value. Remember, +people often respond better to what they get out of it. If you run +into resistance, figure out what those people get out of the other +choice and how Perl might satisfy that requirement. + +You don't have to worry about finding or paying for Perl; it's freely +available and several popular operating systems come with Perl. Community +support in places such as Perlmonks ( http://www.perlmonks.com ) +and the various Perl mailing lists ( http://lists.perl.org ) means that +you can usually get quick answers to your problems. + +Finally, keep in mind that Perl might not be the right tool for every +job. You're a much better advocate if your claims are reasonable and +grounded in reality. Dogmatically advocating anything tends to make +people discount your message. Be honest about possible disadvantages +to your choice of Perl since any choice has trade-offs. + +You might find these links useful: + +=over 4 + +=item * http://perltraining.com.au/whyperl.html + +=item * http://www.perl.org/advocacy/whyperl.html + +=back + +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. =head1 AUTHOR AND COPYRIGHT diff --git a/pod/perlfaq2.pod b/pod/perlfaq2.pod index ed4199615a..45ad2b4a86 100644 --- a/pod/perlfaq2.pod +++ b/pod/perlfaq2.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq2 - Obtaining and Learning about Perl ($Revision: 1.39 $, $Date: 2006/01/08 14:27:07 $) +perlfaq2 - Obtaining and Learning about Perl ($Revision: 3606 $) =head1 DESCRIPTION @@ -514,6 +514,14 @@ http://www.cpan.org/ is the Comprehensive Perl Archive Network, a replicated worldwide repository of Perl software, see the I<What is CPAN?> question earlier in this document. +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and diff --git a/pod/perlfaq3.pod b/pod/perlfaq3.pod index 9f1f5a6f2f..6eea58bf62 100644 --- a/pod/perlfaq3.pod +++ b/pod/perlfaq3.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq3 - Programming Tools ($Revision: 1.56 $, $Date: 2005/12/31 00:54:37 $) +perlfaq3 - Programming Tools ($Revision: 3606 $) =head1 DESCRIPTION @@ -110,28 +110,41 @@ perl finds it. =head2 How do I debug my Perl programs? -Have you tried C<use warnings> or used C<-w>? They enable warnings -to detect dubious practices. +(contributed by brian d foy) + +Before you do anything else, you can help yourself by ensuring that +you let Perl tell you about problem areas in your code. By turning +on warnings and strictures, you can head off many problems before +they get too big. You can find out more about these in L<strict> +and L<warnings>. + + #!/usr/bin/perl + use strict; + use warnings; + +Beyond that, the simplest debugger is the C<print> function. Use it +to look at values as you run your program: + + print STDERR "The value is [$value]\n"; -Have you tried C<use strict>? It prevents you from using symbolic -references, makes you predeclare any subroutines that you call as bare -words, and (probably most importantly) forces you to predeclare your -variables with C<my>, C<our>, or C<use vars>. +The C<Data::Dumper> module can pretty-print Perl data structures: -Did you check the return values of each and every system call? The operating -system (and thus Perl) tells you whether they worked, and if not -why. + use Data::Dumper( Dump ); + print STDERR "The hash is " . Dump( \%hash ) . "\n"; + +Perl comes with an interactive debugger, which you can start with the +C<-d> switch. It's fully explained in L<perldebug>. - open(FH, "> /etc/cantwrite") - or die "Couldn't write to /etc/cantwrite: $!\n"; +If you'd like a graphical user interface and you have Tk, you can use +C<ptkdb>. It's on CPAN and available for free. -Did you read L<perltrap>? It's full of gotchas for old and new Perl -programmers and even has sections for those of you who are upgrading -from languages like I<awk> and I<C>. +If you need something much more sophisicated and controllable, Leon +Brocard's Devel::ebug (which you can call with the -D switch as -Debug) +gives you the programmatic hooks into everything you need to write your +own (without too much pain and suffering). -Have you tried the Perl debugger, described in L<perldebug>? You can -step through your program and see what it's doing and thus work out -why what it's doing isn't what it should be doing. +You can also use a commercial debugger such as Affrus (Mac OS X), Komodo +from Activestate (Windows and Mac OS X), or EPIC (most platforms). =head2 How do I profile my Perl programs? @@ -975,6 +988,14 @@ This module (part of the standard Perl distribution) is designed to write a Makefile for an extension module from a Makefile.PL. For more information, see L<ExtUtils::MakeMaker>. +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and diff --git a/pod/perlfaq4.pod b/pod/perlfaq4.pod index 22ea1ae581..0966139224 100644 --- a/pod/perlfaq4.pod +++ b/pod/perlfaq4.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq4 - Data Manipulation ($Revision: 1.73 $, $Date: 2005/12/31 00:54:37 $) +perlfaq4 - Data Manipulation ($Revision: 3606 $) =head1 DESCRIPTION @@ -362,6 +362,9 @@ pseudorandom generator than comes with your operating system, look at =head2 How do I get a random number between X and Y? +To get a random number between two values, you can use the +C<rand()> builtin to get a random number between 0 and + C<rand($x)> returns a number such that C<< 0 <= rand($x) < $x >>. Thus what you want to have perl figure out is a random number in the range from 0 to the @@ -371,19 +374,19 @@ That is, to get a number between 10 and 15, inclusive, you want a random number between 0 and 5 that you can then add to 10. - my $number = 10 + int rand( 15-10+1 ); + my $number = 10 + int rand( 15-10+1 ); Hence you derive the following simple function to abstract that. It selects a random integer between the two given -integers (inclusive), For example: C<random_int_in(50,120)>. - - sub random_int_in ($$) { - my($min, $max) = @_; - # Assumes that the two arguments are integers themselves! - return $min if $min == $max; - ($min, $max) = ($max, $min) if $min > $max; - return $min + int rand(1 + $max - $min); - } +integers (inclusive), For example: C<random_int_between(50,120)>. + + sub random_int_between ($$) { + my($min, $max) = @_; + # Assumes that the two arguments are integers themselves! + return $min if $min == $max; + ($min, $max) = ($max, $min) if $min > $max; + return $min + int rand(1 + $max - $min); + } =head1 Data: Dates @@ -2153,6 +2156,14 @@ The kgbpack.c code in the PGPLOT module on CPAN does just this. If you're doing a lot of float or double processing, consider using the PDL module from CPAN instead--it makes number-crunching easy. +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and diff --git a/pod/perlfaq5.pod b/pod/perlfaq5.pod index 839234e03c..98be1b05ce 100644 --- a/pod/perlfaq5.pod +++ b/pod/perlfaq5.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq5 - Files and Formats ($Revision: 1.42 $, $Date: 2005/12/31 00:54:37 $) +perlfaq5 - Files and Formats ($Revision: 3606 $) =head1 DESCRIPTION @@ -36,30 +36,30 @@ L<perlvar/$E<verbar>> and L<perlfunc/select>). Use select() to choose the desired handle, then set its per-filehandle variables. - $old_fh = select(OUTPUT_HANDLE); - $| = 1; - select($old_fh); + $old_fh = select(OUTPUT_HANDLE); + $| = 1; + select($old_fh); Some idioms can handle this in a single statement: - select((select(OUTPUT_HANDLE), $| = 1)[0]); + select((select(OUTPUT_HANDLE), $| = 1)[0]); - $| = 1, select $_ for select OUTPUT_HANDLE; + $| = 1, select $_ for select OUTPUT_HANDLE; Some modules offer object-oriented access to handles and their variables, although they may be overkill if this is the only thing you do with them. You can use IO::Handle: - use IO::Handle; - open(DEV, ">/dev/printer"); # but is this? - DEV->autoflush(1); + use IO::Handle; + open(DEV, ">/dev/printer"); # but is this? + DEV->autoflush(1); or IO::Socket: - use IO::Socket; # this one is kinda a pipe? + use IO::Socket; # this one is kinda a pipe? my $sock = IO::Socket::INET->new( 'www.example.com:80' ); - $sock->autoflush(); + $sock->autoflush(); =head2 How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file? X<file, editing> @@ -75,12 +75,12 @@ following program uses a feature of tr///, as documented in L<perlop>. If your text file doesn't end with a newline, then it's not really a proper text file, so this may report one fewer line than you expect. - $lines = 0; - open(FILE, $filename) or die "Can't open `$filename': $!"; - while (sysread FILE, $buffer, 4096) { - $lines += ($buffer =~ tr/\n//); - } - close FILE; + $lines = 0; + open(FILE, $filename) or die "Can't open `$filename': $!"; + while (sysread FILE, $buffer, 4096) { + $lines += ($buffer =~ tr/\n//); + } + close FILE; This assumes no funny games with newline translations. @@ -92,19 +92,19 @@ the behavior of C<< <> >>; see L<perlrun> for more details. By modifying the appropriate variables directly, you can get the same behavior within a larger program. For example: - # ... - { - local($^I, @ARGV) = ('.orig', glob("*.c")); - while (<>) { - if ($. == 1) { - print "This line should appear at the top of each file\n"; - } - s/\b(p)earl\b/${1}erl/i; # Correct typos, preserving case - print; - close ARGV if eof; # Reset $. - } - } - # $^I and @ARGV return to their old values here + # ... + { + local($^I, @ARGV) = ('.orig', glob("*.c")); + while (<>) { + if ($. == 1) { + print "This line should appear at the top of each file\n"; + } + s/\b(p)earl\b/${1}erl/i; # Correct typos, preserving case + print; + close ARGV if eof; # Reset $. + } + } + # $^I and @ARGV return to their old values here This block modifies all the C<.c> files in the current directory, leaving a backup of the original data from each file in a new @@ -138,47 +138,50 @@ creates an anonymous temporary file. Otherwise, you can use the File::Temp module. - use File::Temp qw/ tempfile tempdir /; + use File::Temp qw/ tempfile tempdir /; - $dir = tempdir( CLEANUP => 1 ); - ($fh, $filename) = tempfile( DIR => $dir ); + $dir = tempdir( CLEANUP => 1 ); + ($fh, $filename) = tempfile( DIR => $dir ); - # or if you don't need to know the filename + # or if you don't need to know the filename - $fh = tempfile( DIR => $dir ); + $fh = tempfile( DIR => $dir ); The File::Temp has been a standard module since Perl 5.6.1. If you don't have a modern enough Perl installed, use the C<new_tmpfile> class method from the IO::File module to get a filehandle opened for reading and writing. Use it if you don't need to know the file's name: - use IO::File; - $fh = IO::File->new_tmpfile() + use IO::File; + $fh = IO::File->new_tmpfile() or die "Unable to make new temporary file: $!"; If you're committed to creating a temporary file by hand, use the process ID and/or the current time-value. If you need to have many temporary files in one process, use a counter: - BEGIN { + BEGIN { use Fcntl; my $temp_dir = -d '/tmp' ? '/tmp' : $ENV{TMPDIR} || $ENV{TEMP}; my $base_name = sprintf("%s/%d-%d-0000", $temp_dir, $$, time()); + sub temp_file { - local *FH; - my $count = 0; - until (defined(fileno(FH)) || $count++ > 100) { + local *FH; + my $count = 0; + until (defined(fileno(FH)) || $count++ > 100) { $base_name =~ s/-(\d+)$/"-" . (1 + $1)/e; # O_EXCL is required for security reasons. sysopen(FH, $base_name, O_WRONLY|O_EXCL|O_CREAT); - } - if (defined(fileno(FH)) + } + + if (defined(fileno(FH)) return (*FH, $base_name); - } else { + } + else { return (); } } - } + } =head2 How can I manipulate fixed-record-length files? X<fixed-length> X<file, fixed-length records> @@ -192,27 +195,27 @@ Here is a sample chunk of code to break up and put back together again some fixed-format input lines, in this case from the output of a normal, Berkeley-style ps: - # sample input line: - # 15158 p5 T 0:00 perl /home/tchrist/scripts/now-what - my $PS_T = 'A6 A4 A7 A5 A*'; - open my $ps, '-|', 'ps'; - print scalar <$ps>; - my @fields = qw( pid tt stat time command ); - while (<$ps>) { - my %process; - @process{@fields} = unpack($PS_T, $_); + # sample input line: + # 15158 p5 T 0:00 perl /home/tchrist/scripts/now-what + my $PS_T = 'A6 A4 A7 A5 A*'; + open my $ps, '-|', 'ps'; + print scalar <$ps>; + my @fields = qw( pid tt stat time command ); + while (<$ps>) { + my %process; + @process{@fields} = unpack($PS_T, $_); for my $field ( @fields ) { - print "$field: <$process{$field}>\n"; + print "$field: <$process{$field}>\n"; } print 'line=', pack($PS_T, @process{@fields} ), "\n"; - } + } We've used a hash slice in order to easily handle the fields of each row. Storing the keys in an array means it's easy to operate on them as a group or loop over them with for. It also avoids polluting the program with global variables and using symbolic references. -=head2 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? +=head2 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? X<filehandle, local> X<filehandle, passing> X<filehandle, reference> As of perl5.6, open() autovivifies file and directory handles @@ -228,6 +231,19 @@ and use them in the place of named handles. process_file( $fh ); +If you like, you can store these filehandles in an array or a hash. +If you access them directly, they aren't simple scalars and you +need to give C<print> a little help by placing the filehandle +reference in braces. Perl can only figure it out on its own when +the filehandle reference is a simple scalar. + + my @fhs = ( $fh1, $fh2, $fh3 ); + + for( $i = 0; $i <= $#fhs; $i++ ) { + print {$fhs[$i]} "just another Perl answer, \n"; + } + + Before perl5.6, you had to deal with various typeglob idioms which you may see in older code. @@ -248,18 +264,18 @@ An indirect filehandle is using something other than a symbol in a place that a filehandle is expected. Here are ways to get indirect filehandles: - $fh = SOME_FH; # bareword is strict-subs hostile - $fh = "SOME_FH"; # strict-refs hostile; same package only - $fh = *SOME_FH; # typeglob - $fh = \*SOME_FH; # ref to typeglob (bless-able) - $fh = *SOME_FH{IO}; # blessed IO::Handle from *SOME_FH typeglob + $fh = SOME_FH; # bareword is strict-subs hostile + $fh = "SOME_FH"; # strict-refs hostile; same package only + $fh = *SOME_FH; # typeglob + $fh = \*SOME_FH; # ref to typeglob (bless-able) + $fh = *SOME_FH{IO}; # blessed IO::Handle from *SOME_FH typeglob Or, you can use the C<new> method from one of the IO::* modules to create an anonymous filehandle, store that in a scalar variable, and use it as though it were a normal filehandle. - use IO::Handle; # 5.004 or higher - $fh = IO::Handle->new(); + use IO::Handle; # 5.004 or higher + $fh = IO::Handle->new(); Then use any of those as you would a normal filehandle. Anywhere that Perl is expecting a filehandle, an indirect filehandle may be used @@ -268,32 +284,32 @@ a filehandle. Functions like C<print>, C<open>, C<seek>, or the C<< <FH> >> diamond operator will accept either a named filehandle or a scalar variable containing one: - ($ifh, $ofh, $efh) = (*STDIN, *STDOUT, *STDERR); - print $ofh "Type it: "; - $got = <$ifh> - print $efh "What was that: $got"; + ($ifh, $ofh, $efh) = (*STDIN, *STDOUT, *STDERR); + print $ofh "Type it: "; + $got = <$ifh> + print $efh "What was that: $got"; If you're passing a filehandle to a function, you can write the function in two ways: - sub accept_fh { - my $fh = shift; - print $fh "Sending to indirect filehandle\n"; - } + sub accept_fh { + my $fh = shift; + print $fh "Sending to indirect filehandle\n"; + } Or it can localize a typeglob and use the filehandle directly: - sub accept_fh { - local *FH = shift; - print FH "Sending to localized filehandle\n"; - } + sub accept_fh { + local *FH = shift; + print FH "Sending to localized filehandle\n"; + } Both styles work with either objects or typeglobs of real filehandles. (They might also work with strings under some circumstances, but this is risky.) - accept_fh(*STDOUT); - accept_fh($handle); + accept_fh(*STDOUT); + accept_fh($handle); In the examples above, we assigned the filehandle to a scalar variable before using it. That is because only simple scalar variables, not @@ -302,24 +318,24 @@ built-ins like C<print>, C<printf>, or the diamond operator. Using something other than a simple scalar variable as a filehandle is illegal and won't even compile: - @fd = (*STDIN, *STDOUT, *STDERR); - print $fd[1] "Type it: "; # WRONG - $got = <$fd[0]> # WRONG - print $fd[2] "What was that: $got"; # WRONG + @fd = (*STDIN, *STDOUT, *STDERR); + print $fd[1] "Type it: "; # WRONG + $got = <$fd[0]> # WRONG + print $fd[2] "What was that: $got"; # WRONG With C<print> and C<printf>, you get around this by using a block and an expression where you would place the filehandle: - print { $fd[1] } "funny stuff\n"; - printf { $fd[1] } "Pity the poor %x.\n", 3_735_928_559; - # Pity the poor deadbeef. + print { $fd[1] } "funny stuff\n"; + printf { $fd[1] } "Pity the poor %x.\n", 3_735_928_559; + # Pity the poor deadbeef. That block is a proper block like any other, so you can put more complicated code there. This sends the message out to one of two places: - $ok = -x "/bin/cat"; - print { $ok ? $fd[1] : $fd[2] } "cat stat $ok\n"; - print { $fd[ 1+ ($ok || 0) ] } "cat stat $ok\n"; + $ok = -x "/bin/cat"; + print { $ok ? $fd[1] : $fd[2] } "cat stat $ok\n"; + print { $fd[ 1+ ($ok || 0) ] } "cat stat $ok\n"; This approach of treating C<print> and C<printf> like object methods calls doesn't work for the diamond operator. That's because it's a @@ -330,7 +346,7 @@ as C<< <> >> does. Given the initialization shown above for @fd, this would work, but only because readline() requires a typeglob. It doesn't work with objects or strings, which might be a bug we haven't fixed yet. - $got = readline($fd[0]); + $got = readline($fd[0]); Let it be noted that the flakiness of indirect filehandles is not related to whether they're strings, typeglobs, objects, or anything else. @@ -361,28 +377,28 @@ really). This subroutine will add commas to your number: sub commify { - local $_ = shift; - 1 while s/^([-+]?\d+)(\d{3})/$1,$2/; - return $_; - } + local $_ = shift; + 1 while s/^([-+]?\d+)(\d{3})/$1,$2/; + return $_; + } This regex from Benjamin Goldberg will add commas to numbers: - s/(^[-+]?\d+?(?=(?>(?:\d{3})+)(?!\d))|\G\d{3}(?=\d))/$1,/g; + s/(^[-+]?\d+?(?=(?>(?:\d{3})+)(?!\d))|\G\d{3}(?=\d))/$1,/g; It is easier to see with comments: - s/( - ^[-+]? # beginning of number. - \d+? # first digits before first comma - (?= # followed by, (but not included in the match) : - (?>(?:\d{3})+) # some positive multiple of three digits. - (?!\d) # an *exact* multiple, not x * 3 + 1 or whatever. - ) - | # or: - \G\d{3} # after the last group, get three digits - (?=\d) # but they have to have more digits after them. - )/$1,/xg; + s/( + ^[-+]? # beginning of number. + \d+? # first digits before first comma + (?= # followed by, (but not included in the match) : + (?>(?:\d{3})+) # some positive multiple of three digits. + (?!\d) # an *exact* multiple, not x * 3 + 1 or whatever. + ) + | # or: + \G\d{3} # after the last group, get three digits + (?=\d) # but they have to have more digits after them. + )/$1,/xg; =head2 How can I translate tildes (~) in a filename? X<tilde> X<tilde expansion> @@ -413,12 +429,12 @@ X<clobber> X<read-write> X<clobbering> X<truncate> X<truncating> Because you're using something like this, which truncates the file and I<then> gives you read-write access: - open(FH, "+> /path/name"); # WRONG (almost always) + open(FH, "+> /path/name"); # WRONG (almost always) Whoops. You should instead use this, which will fail if the file doesn't exist. - open(FH, "+< /path/name"); # open for update + open(FH, "+< /path/name"); # open for update Using ">" always clobbers or creates. Using "<" never does either. The "+" doesn't change this. @@ -426,52 +442,52 @@ either. The "+" doesn't change this. Here are examples of many kinds of file opens. Those using sysopen() all assume - use Fcntl; + use Fcntl; To open file for reading: - open(FH, "< $path") || die $!; - sysopen(FH, $path, O_RDONLY) || die $!; + open(FH, "< $path") || die $!; + sysopen(FH, $path, O_RDONLY) || die $!; To open file for writing, create new file if needed or else truncate old file: - open(FH, "> $path") || die $!; - sysopen(FH, $path, O_WRONLY|O_TRUNC|O_CREAT) || die $!; - sysopen(FH, $path, O_WRONLY|O_TRUNC|O_CREAT, 0666) || die $!; + open(FH, "> $path") || die $!; + sysopen(FH, $path, O_WRONLY|O_TRUNC|O_CREAT) || die $!; + sysopen(FH, $path, O_WRONLY|O_TRUNC|O_CREAT, 0666) || die $!; To open file for writing, create new file, file must not exist: - sysopen(FH, $path, O_WRONLY|O_EXCL|O_CREAT) || die $!; - sysopen(FH, $path, O_WRONLY|O_EXCL|O_CREAT, 0666) || die $!; + sysopen(FH, $path, O_WRONLY|O_EXCL|O_CREAT) || die $!; + sysopen(FH, $path, O_WRONLY|O_EXCL|O_CREAT, 0666) || die $!; To open file for appending, create if necessary: - open(FH, ">> $path") || die $!; - sysopen(FH, $path, O_WRONLY|O_APPEND|O_CREAT) || die $!; - sysopen(FH, $path, O_WRONLY|O_APPEND|O_CREAT, 0666) || die $!; + open(FH, ">> $path") || die $!; + sysopen(FH, $path, O_WRONLY|O_APPEND|O_CREAT) || die $!; + sysopen(FH, $path, O_WRONLY|O_APPEND|O_CREAT, 0666) || die $!; To open file for appending, file must exist: - sysopen(FH, $path, O_WRONLY|O_APPEND) || die $!; + sysopen(FH, $path, O_WRONLY|O_APPEND) || die $!; To open file for update, file must exist: - open(FH, "+< $path") || die $!; - sysopen(FH, $path, O_RDWR) || die $!; + open(FH, "+< $path") || die $!; + sysopen(FH, $path, O_RDWR) || die $!; To open file for update, create file if necessary: - sysopen(FH, $path, O_RDWR|O_CREAT) || die $!; - sysopen(FH, $path, O_RDWR|O_CREAT, 0666) || die $!; + sysopen(FH, $path, O_RDWR|O_CREAT) || die $!; + sysopen(FH, $path, O_RDWR|O_CREAT, 0666) || die $!; To open file for update, file must not exist: - sysopen(FH, $path, O_RDWR|O_EXCL|O_CREAT) || die $!; - sysopen(FH, $path, O_RDWR|O_EXCL|O_CREAT, 0666) || die $!; + sysopen(FH, $path, O_RDWR|O_EXCL|O_CREAT) || die $!; + sysopen(FH, $path, O_RDWR|O_EXCL|O_CREAT, 0666) || die $!; To open a file without blocking, creating if necessary: - sysopen(FH, "/foo/somefile", O_WRONLY|O_NDELAY|O_CREAT) + sysopen(FH, "/foo/somefile", O_WRONLY|O_NDELAY|O_CREAT) or die "can't open /foo/somefile: $!": Be warned that neither creation nor deletion of files is guaranteed to @@ -526,7 +542,7 @@ X<rename> X<mv> X<move> X<file, rename> X<ren> If your operating system supports a proper mv(1) utility or its functional equivalent, this works: - rename($old, $new) or system("mv", $old, $new); + rename($old, $new) or system("mv", $old, $new); It may be more portable to use the File::Copy module instead. You just copy to the new file to the new name (checking return @@ -589,14 +605,14 @@ X<lock, lockfile race condition> A common bit of code B<NOT TO USE> is this: - sleep(3) while -e "file.lock"; # PLEASE DO NOT USE - open(LCK, "> file.lock"); # THIS BROKEN CODE + sleep(3) while -e "file.lock"; # PLEASE DO NOT USE + open(LCK, "> file.lock"); # THIS BROKEN CODE This is a classic race condition: you take two steps to do something which must be done in one. That's why computer hardware provides an atomic test-and-set instruction. In theory, this "ought" to work: - sysopen(FH, "file.lock", O_WRONLY|O_EXCL|O_CREAT) + sysopen(FH, "file.lock", O_WRONLY|O_EXCL|O_CREAT) or die "can't open file.lock: $!"; except that lamentably, file creation (and deletion) is not atomic @@ -614,18 +630,18 @@ they're more realistic. Anyway, this is what you can do if you can't help yourself. - use Fcntl qw(:DEFAULT :flock); - sysopen(FH, "numfile", O_RDWR|O_CREAT) or die "can't open numfile: $!"; - flock(FH, LOCK_EX) or die "can't flock numfile: $!"; - $num = <FH> || 0; - seek(FH, 0, 0) or die "can't rewind numfile: $!"; - truncate(FH, 0) or die "can't truncate numfile: $!"; - (print FH $num+1, "\n") or die "can't write numfile: $!"; - close FH or die "can't close numfile: $!"; + use Fcntl qw(:DEFAULT :flock); + sysopen(FH, "numfile", O_RDWR|O_CREAT) or die "can't open numfile: $!"; + flock(FH, LOCK_EX) or die "can't flock numfile: $!"; + $num = <FH> || 0; + seek(FH, 0, 0) or die "can't rewind numfile: $!"; + truncate(FH, 0) or die "can't truncate numfile: $!"; + (print FH $num+1, "\n") or die "can't write numfile: $!"; + close FH or die "can't close numfile: $!"; Here's a much better web-page hit counter: - $hits = int( (time() - 850_000_000) / rand(1_000) ); + $hits = int( (time() - 850_000_000) / rand(1_000) ); If the count doesn't impress your friends, then the code might. :-) @@ -664,20 +680,20 @@ X<file, binary patch> If you're just trying to patch a binary, in many cases something as simple as this works: - perl -i -pe 's{window manager}{window mangler}g' /usr/bin/emacs + perl -i -pe 's{window manager}{window mangler}g' /usr/bin/emacs However, if you have fixed sized records, then you might do something more like this: - $RECSIZE = 220; # size of record, in bytes - $recno = 37; # which record to update - open(FH, "+<somewhere") || die "can't update somewhere: $!"; - seek(FH, $recno * $RECSIZE, 0); - read(FH, $record, $RECSIZE) == $RECSIZE || die "can't read record $recno: $!"; - # munge the record - seek(FH, -$RECSIZE, 1); - print FH $record; - close FH; + $RECSIZE = 220; # size of record, in bytes + $recno = 37; # which record to update + open(FH, "+<somewhere") || die "can't update somewhere: $!"; + seek(FH, $recno * $RECSIZE, 0); + read(FH, $record, $RECSIZE) == $RECSIZE || die "can't read record $recno: $!"; + # munge the record + seek(FH, -$RECSIZE, 1); + print FH $record; + close FH; Locking and error checking are left as an exercise for the reader. Don't forget them or you'll be quite sorry. @@ -699,18 +715,18 @@ human-readable form. Here's an example: - $write_secs = (stat($file))[9]; - printf "file %s updated at %s\n", $file, + $write_secs = (stat($file))[9]; + printf "file %s updated at %s\n", $file, scalar localtime($write_secs); If you prefer something more legible, use the File::stat module (part of the standard distribution in version 5.004 and later): - # error checking left as an exercise for reader. - use File::stat; - use Time::localtime; - $date_string = ctime(stat($file)->mtime); - print "file $file updated at $date_string\n"; + # error checking left as an exercise for reader. + use File::stat; + use Time::localtime; + $date_string = ctime(stat($file)->mtime); + print "file $file updated at $date_string\n"; The POSIX::strftime() approach has the benefit of being, in theory, independent of the current locale. See L<perllocale> @@ -724,12 +740,12 @@ By way of example, here's a little program that copies the read and write times from its first argument to all the rest of them. - if (@ARGV < 2) { - die "usage: cptimes timestamp_file other_files ...\n"; - } - $timestamp = shift; - ($atime, $mtime) = (stat($timestamp))[8,9]; - utime $atime, $mtime, @ARGV; + if (@ARGV < 2) { + die "usage: cptimes timestamp_file other_files ...\n"; + } + $timestamp = shift; + ($atime, $mtime) = (stat($timestamp))[8,9]; + utime $atime, $mtime, @ARGV; Error checking is, as usual, left as an exercise for the reader. @@ -751,7 +767,7 @@ you can use the IO::Tee or Tie::FileHandle::Multiplex modules. If you only have to do this once, you can print individually to each filehandle. - for $fh (FH1, FH2, FH3) { print $fh "whatever\n" } + for $fh (FH1, FH2, FH3) { print $fh "whatever\n" } =head2 How can I read in an entire file all at once? X<slurp> X<file, slurping> @@ -761,24 +777,24 @@ You can use the File::Slurp module to do it in one step. use File::Slurp; $all_of_it = read_file($filename); # entire file in scalar - @all_lines = read_file($filename); # one line perl element + @all_lines = read_file($filename); # one line perl element The customary Perl approach for processing all the lines in a file is to do so one line at a time: - open (INPUT, $file) || die "can't open $file: $!"; - while (<INPUT>) { - chomp; - # do something with $_ - } - close(INPUT) || die "can't close $file: $!"; + open (INPUT, $file) || die "can't open $file: $!"; + while (<INPUT>) { + chomp; + # do something with $_ + } + close(INPUT) || die "can't close $file: $!"; This is tremendously more efficient than reading the entire file into memory as an array of lines and then processing it one element at a time, which is often--if not almost always--the wrong approach. Whenever you see someone do this: - @lines = <INPUT>; + @lines = <INPUT>; you should think long and hard about why you need everything loaded at once. It's just not a scalable solution. You might also find it more @@ -789,16 +805,16 @@ line in the file. You can read the entire filehandle contents into a scalar. - { + { local(*INPUT, $/); open (INPUT, $file) || die "can't open $file: $!"; $var = <INPUT>; - } + } That temporarily undefs your record separator, and will automatically close the file at block exit. If the file is already open, just use this: - $var = do { local $/; <INPUT> }; + $var = do { local $/; <INPUT> }; For ordinary files you can also use the read function. @@ -830,18 +846,18 @@ If your system supports the portable operating system programming interface (POSIX), you can use the following code, which you'll note turns off echo processing as well. - #!/usr/bin/perl -w - use strict; - $| = 1; - for (1..4) { - my $got; - print "gimme: "; - $got = getone(); - print "--> $got\n"; - } + #!/usr/bin/perl -w + use strict; + $| = 1; + for (1..4) { + my $got; + print "gimme: "; + $got = getone(); + print "--> $got\n"; + } exit; - BEGIN { + BEGIN { use POSIX qw(:termios_h); my ($term, $oterm, $echo, $noecho, $fd_stdin); @@ -856,40 +872,40 @@ turns off echo processing as well. $noecho = $oterm & ~$echo; sub cbreak { - $term->setlflag($noecho); - $term->setcc(VTIME, 1); - $term->setattr($fd_stdin, TCSANOW); - } - + $term->setlflag($noecho); + $term->setcc(VTIME, 1); + $term->setattr($fd_stdin, TCSANOW); + } + sub cooked { - $term->setlflag($oterm); - $term->setcc(VTIME, 0); - $term->setattr($fd_stdin, TCSANOW); - } + $term->setlflag($oterm); + $term->setcc(VTIME, 0); + $term->setattr($fd_stdin, TCSANOW); + } sub getone { - my $key = ''; - cbreak(); - sysread(STDIN, $key, 1); - cooked(); - return $key; - } + my $key = ''; + cbreak(); + sysread(STDIN, $key, 1); + cooked(); + return $key; + } - } + } - END { cooked() } + END { cooked() } The Term::ReadKey module from CPAN may be easier to use. Recent versions include also support for non-portable systems as well. - use Term::ReadKey; - open(TTY, "</dev/tty"); - print "Gimme a char: "; - ReadMode "raw"; - $key = ReadKey 0, *TTY; - ReadMode "normal"; - printf "\nYou said %s, char number %03d\n", - $key, ord $key; + use Term::ReadKey; + open(TTY, "</dev/tty"); + print "Gimme a char: "; + ReadMode "raw"; + $key = ReadKey 0, *TTY; + ReadMode "normal"; + printf "\nYou said %s, char number %03d\n", + $key, ord $key; =head2 How can I tell whether there's a character waiting on a filehandle? @@ -903,11 +919,11 @@ comp.unix.* for things like this: the answer is essentially the same. It's very system dependent. Here's one solution that works on BSD systems: - sub key_ready { - my($rin, $nfd); - vec($rin, fileno(STDIN), 1) = 1; - return $nfd = select($rin,undef,undef,0); - } + sub key_ready { + my($rin, $nfd); + vec($rin, fileno(STDIN), 1) = 1; + return $nfd = select($rin,undef,undef,0); + } If you want to find out how many characters are waiting, there's also the FIONREAD ioctl call to be looked at. The I<h2ph> tool that @@ -915,37 +931,37 @@ comes with Perl tries to convert C include files to Perl code, which can be C<require>d. FIONREAD ends up defined as a function in the I<sys/ioctl.ph> file: - require 'sys/ioctl.ph'; + require 'sys/ioctl.ph'; - $size = pack("L", 0); - ioctl(FH, FIONREAD(), $size) or die "Couldn't call ioctl: $!\n"; - $size = unpack("L", $size); + $size = pack("L", 0); + ioctl(FH, FIONREAD(), $size) or die "Couldn't call ioctl: $!\n"; + $size = unpack("L", $size); If I<h2ph> wasn't installed or doesn't work for you, you can I<grep> the include files by hand: - % grep FIONREAD /usr/include/*/* - /usr/include/asm/ioctls.h:#define FIONREAD 0x541B + % grep FIONREAD /usr/include/*/* + /usr/include/asm/ioctls.h:#define FIONREAD 0x541B Or write a small C program using the editor of champions: - % cat > fionread.c - #include <sys/ioctl.h> - main() { - printf("%#08x\n", FIONREAD); - } - ^D - % cc -o fionread fionread.c - % ./fionread - 0x4004667f + % cat > fionread.c + #include <sys/ioctl.h> + main() { + printf("%#08x\n", FIONREAD); + } + ^D + % cc -o fionread fionread.c + % ./fionread + 0x4004667f And then hard code it, leaving porting as an exercise to your successor. - $FIONREAD = 0x4004667f; # XXX: opsys dependent + $FIONREAD = 0x4004667f; # XXX: opsys dependent - $size = pack("L", 0); - ioctl(FH, $FIONREAD, $size) or die "Couldn't call ioctl: $!\n"; - $size = unpack("L", $size); + $size = pack("L", 0); + ioctl(FH, $FIONREAD, $size) or die "Couldn't call ioctl: $!\n"; + $size = unpack("L", $size); FIONREAD requires a filehandle connected to a stream, meaning that sockets, pipes, and tty devices work, but I<not> files. @@ -955,7 +971,7 @@ X<tail> First try - seek(GWFILE, 0, 1); + seek(GWFILE, 0, 1); The statement C<seek(GWFILE, 0, 1)> doesn't change the current position, but it does clear the end-of-file condition on the handle, so that the @@ -985,8 +1001,8 @@ X<dup> If you check L<perlfunc/open>, you'll see that several of the ways to call open() should do the trick. For example: - open(LOG, ">>/foo/logfile"); - open(STDERR, ">&LOG"); + open(LOG, ">>/foo/logfile"); + open(STDERR, ">&LOG"); Or even with a literal numeric descriptor: @@ -1008,17 +1024,17 @@ used for things that Perl opened itself, even if it was a dup of a numeric descriptor as with MHCONTEXT above. But if you really have to, you may be able to do this: - require 'sys/syscall.ph'; - $rc = syscall(&SYS_close, $fd + 0); # must force numeric - die "can't sysclose $fd: $!" unless $rc == -1; + require 'sys/syscall.ph'; + $rc = syscall(&SYS_close, $fd + 0); # must force numeric + die "can't sysclose $fd: $!" unless $rc == -1; Or, just use the fdopen(3S) feature of open(): - { + { local *F; open F, "<&=$fd" or die "Cannot reopen fd=$fd: $!"; close F; - } + } =head2 Why can't I use "C:\temp\foo" in DOS paths? Why doesn't `C:\temp\foo.exe` work? X<filename, DOS issues> @@ -1065,8 +1081,8 @@ X<file, selecting a random line> Here's an algorithm from the Camel Book: - srand; - rand($.) < 1 && ($line = $_) while <>; + srand; + rand($.) < 1 && ($line = $_) while <>; This has a significant advantage in space over reading the whole file in. You can find a proof of this method in I<The Art of Computer @@ -1085,24 +1101,32 @@ file as an array. Simply access a random array element. Saying - print "@lines\n"; + print "@lines\n"; joins together the elements of C<@lines> with a space between them. If C<@lines> were C<("little", "fluffy", "clouds")> then the above statement would print - little fluffy clouds + little fluffy clouds but if each element of C<@lines> was a line of text, ending a newline character C<("little\n", "fluffy\n", "clouds\n")> then it would print: - little - fluffy - clouds + little + fluffy + clouds If your array contains lines, just print them: - print @lines; + print @lines; + +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. =head1 AUTHOR AND COPYRIGHT diff --git a/pod/perlfaq6.pod b/pod/perlfaq6.pod index 72c26092ad..b07c522389 100644 --- a/pod/perlfaq6.pod +++ b/pod/perlfaq6.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq6 - Regular Expressions ($Revision: 1.38 $, $Date: 2005/12/31 00:54:37 $) +perlfaq6 - Regular Expressions ($Revision: 3606 $) =head1 DESCRIPTION @@ -887,6 +887,14 @@ in L<perlre>. } close FILE; +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and diff --git a/pod/perlfaq7.pod b/pod/perlfaq7.pod index 3933f57940..9d9ef8d554 100644 --- a/pod/perlfaq7.pod +++ b/pod/perlfaq7.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq7 - General Perl Language Issues ($Revision: 1.28 $, $Date: 2005/12/31 00:54:37 $) +perlfaq7 - General Perl Language Issues ($Revision: 3606 $) =head1 DESCRIPTION @@ -960,6 +960,14 @@ If you get a message like "perl: command not found", perl is not in your PATH, which might also mean that the location of perl is not where you expect it so you need to adjust your shebang line. +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and diff --git a/pod/perlfaq8.pod b/pod/perlfaq8.pod index cc65a1fe8f..06494e240f 100644 --- a/pod/perlfaq8.pod +++ b/pod/perlfaq8.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq8 - System Interaction ($Revision: 1.27 $, $Date: 2005/12/31 00:54:37 $) +perlfaq8 - System Interaction ($Revision: 3606 $) =head1 DESCRIPTION @@ -1251,6 +1251,14 @@ It's a perl4-style file defining values for system networking constants. Sometimes it is built using h2ph when Perl is installed, but other times it is not. Modern programs C<use Socket;> instead. +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and diff --git a/pod/perlfaq9.pod b/pod/perlfaq9.pod index 27aa8d4f25..f017a40879 100644 --- a/pod/perlfaq9.pod +++ b/pod/perlfaq9.pod @@ -1,6 +1,6 @@ =head1 NAME -perlfaq9 - Networking ($Revision: 1.28 $, $Date: 2005/12/31 00:54:37 $) +perlfaq9 - Networking ($Revision: 3606 $) =head1 DESCRIPTION @@ -647,6 +647,14 @@ available from CPAN) is more complex but can put as well as fetch. Use one of the RPC modules you can find on CPAN ( http://search.cpan.org/search?query=RPC&mode=all ). +=head1 REVISION + +Revision: $Revision: 3606 $ + +Date: $Date: 2006-03-06 12:05:47 +0100 (lun, 06 mar 2006) $ + +See L<perlfaq> for source control details and availability. + =head1 AUTHOR AND COPYRIGHT Copyright (c) 1997-2006 Tom Christiansen, Nathan Torkington, and |