Adding upstream version 4.22.0.upstream/4.22.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 796 insertions, 0 deletions

diff --git a/upstream/debian-bookworm/man1/perlfaq.1 b/upstream/debian-bookworm/man1/perlfaq.1
new file mode 100644
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@@ -0,0 +1,796 @@
+.\" Automatically generated by Pod::Man 4.14 (Pod::Simple 3.43)
+.\"
+.\" Standard preamble:
+.\" ========================================================================
+.de Sp \" Vertical space (when we can't use .PP)
+.if t .sp .5v
+.if n .sp
+..
+.de Vb \" Begin verbatim text
+.ft CW
+.nf
+.ne \\$1
+..
+.de Ve \" End verbatim text
+.ft R
+.fi
+..
+.\" Set up some character translations and predefined strings.  \*(-- will
+.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
+.\" double quote, and \*(R" will give a right double quote.  \*(C+ will
+.\" give a nicer C++.  Capital omega is used to do unbreakable dashes and
+.\" therefore won't be available.  \*(C` and \*(C' expand to `' in nroff,
+.\" nothing in troff, for use with C<>.
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+.    ds -- \(*W-
+.    ds PI pi
+.    if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
+.    if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\"  diablo 12 pitch
+.    ds L" ""
+.    ds R" ""
+.    ds C` ""
+.    ds C' ""
+'br\}
+.el\{\
+.    ds -- \|\(em\|
+.    ds PI \(*p
+.    ds L" ``
+.    ds R" ''
+.    ds C`
+.    ds C'
+'br\}
+.\"
+.\" Escape single quotes in literal strings from groff's Unicode transform.
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.\"
+.\" If the F register is >0, we'll generate index entries on stderr for
+.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
+.\" entries marked with X<> in POD.  Of course, you'll have to process the
+.\" output yourself in some meaningful fashion.
+.\"
+.\" Avoid warning from groff about undefined register 'F'.
+.de IX
+..
+.nr rF 0
+.if \n(.g .if rF .nr rF 1
+.if (\n(rF:(\n(.g==0)) \{\
+.    if \nF \{\
+.        de IX
+.        tm Index:\\$1\t\\n%\t"\\$2"
+..
+.        if !\nF==2 \{\
+.            nr % 0
+.            nr F 2
+.        \}
+.    \}
+.\}
+.rr rF
+.\" ========================================================================
+.\"
+.IX Title "PERLFAQ 1"
+.TH PERLFAQ 1 "2023-11-25" "perl v5.36.0" "Perl Programmers Reference Guide"
+.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
+.\" way too many mistakes in technical documents.
+.if n .ad l
+.nh
+.SH "NAME"
+perlfaq \- Frequently asked questions about Perl
+.SH "VERSION"
+.IX Header "VERSION"
+version 5.20210520
+.SH "DESCRIPTION"
+.IX Header "DESCRIPTION"
+The perlfaq comprises several documents that answer the most commonly
+asked questions about Perl and Perl programming. It's divided by topic
+into nine major sections outlined in this document.
+.SS "Where to find the perlfaq"
+.IX Subsection "Where to find the perlfaq"
+The perlfaq is an evolving document.  Read the latest version at
+<https://perldoc.perl.org/perlfaq>.  It is also included in the standard Perl
+distribution.
+.SS "How to use the perlfaq"
+.IX Subsection "How to use the perlfaq"
+The \f(CW\*(C`perldoc\*(C'\fR command line tool is part of the standard Perl distribution. To
+read the perlfaq:
+.PP
+.Vb 1
+\&    $ perldoc perlfaq
+.Ve
+.PP
+To search the perlfaq question headings:
+.PP
+.Vb 1
+\&    $ perldoc \-q open
+.Ve
+.SS "How to contribute to the perlfaq"
+.IX Subsection "How to contribute to the perlfaq"
+Review <https://github.com/perl\-doc\-cats/perlfaq/wiki>.  If you don't find
+your suggestion create an issue or pull request against
+<https://github.com/perl\-doc\-cats/perlfaq>.
+.PP
+Once approved, changes will be distributed with the next Perl release and
+subsequently appear at <https://perldoc.perl.org/perlfaq>.
+.SS "What if my question isn't answered in the \s-1FAQ\s0?"
+.IX Subsection "What if my question isn't answered in the FAQ?"
+Try the resources in perlfaq2.
+.SH "TABLE OF CONTENTS"
+.IX Header "TABLE OF CONTENTS"
+.IP "perlfaq1 \- General Questions About Perl" 4
+.IX Item "perlfaq1 - General Questions About Perl"
+.PD 0
+.IP "perlfaq2 \- Obtaining and Learning about Perl" 4
+.IX Item "perlfaq2 - Obtaining and Learning about Perl"
+.IP "perlfaq3 \- Programming Tools" 4
+.IX Item "perlfaq3 - Programming Tools"
+.IP "perlfaq4 \- Data Manipulation" 4
+.IX Item "perlfaq4 - Data Manipulation"
+.IP "perlfaq5 \- Files and Formats" 4
+.IX Item "perlfaq5 - Files and Formats"
+.IP "perlfaq6 \- Regular Expressions" 4
+.IX Item "perlfaq6 - Regular Expressions"
+.IP "perlfaq7 \- General Perl Language Issues" 4
+.IX Item "perlfaq7 - General Perl Language Issues"
+.IP "perlfaq8 \- System Interaction" 4
+.IX Item "perlfaq8 - System Interaction"
+.IP "perlfaq9 \- Web, Email and Networking" 4
+.IX Item "perlfaq9 - Web, Email and Networking"
+.PD
+.SH "THE QUESTIONS"
+.IX Header "THE QUESTIONS"
+.SS "perlfaq1: General Questions About Perl"
+.IX Subsection "perlfaq1: General Questions About Perl"
+This section of the \s-1FAQ\s0 answers very general, high-level questions about Perl.
+.IP "\(bu" 4
+What is Perl?
+.IP "\(bu" 4
+Who supports Perl? Who develops it? Why is it free?
+.IP "\(bu" 4
+Which version of Perl should I use?
+.IP "\(bu" 4
+What are Perl 4, Perl 5, or Raku (Perl 6)?
+.IP "\(bu" 4
+What is Raku (Perl 6)?
+.IP "\(bu" 4
+How stable is Perl?
+.IP "\(bu" 4
+How often are new versions of Perl released?
+.IP "\(bu" 4
+Is Perl difficult to learn?
+.IP "\(bu" 4
+How does Perl compare with other languages like Java, Python, \s-1REXX,\s0 Scheme, or Tcl?
+.IP "\(bu" 4
+Can I do [task] in Perl?
+.IP "\(bu" 4
+When shouldn't I program in Perl?
+.IP "\(bu" 4
+What's the difference between \*(L"perl\*(R" and \*(L"Perl\*(R"?
+.IP "\(bu" 4
+What is a \s-1JAPH\s0?
+.IP "\(bu" 4
+How can I convince others to use Perl?
+.SS "perlfaq2: Obtaining and Learning about Perl"
+.IX Subsection "perlfaq2: Obtaining and Learning about Perl"
+This section of the \s-1FAQ\s0 answers questions about where to find source and documentation for Perl, support, and related matters.
+.IP "\(bu" 4
+What machines support Perl? Where do I get it?
+.IP "\(bu" 4
+How can I get a binary version of Perl?
+.IP "\(bu" 4
+I don't have a C compiler. How can I build my own Perl interpreter?
+.IP "\(bu" 4
+I copied the Perl binary from one machine to another, but scripts don't work.
+.IP "\(bu" 4
+I grabbed the sources and tried to compile but gdbm/dynamic loading/malloc/linking/... failed. How do I make it work?
+.IP "\(bu" 4
+What modules and extensions are available for Perl? What is \s-1CPAN\s0?
+.IP "\(bu" 4
+Where can I get information on Perl?
+.IP "\(bu" 4
+What is perl.com? Perl Mongers? pm.org? perl.org? cpan.org?
+.IP "\(bu" 4
+Where can I post questions?
+.IP "\(bu" 4
+Perl Books
+.IP "\(bu" 4
+Which magazines have Perl content?
+.IP "\(bu" 4
+Which Perl blogs should I read?
+.IP "\(bu" 4
+What mailing lists are there for Perl?
+.IP "\(bu" 4
+Where can I buy a commercial version of Perl?
+.IP "\(bu" 4
+Where do I send bug reports?
+.SS "perlfaq3: Programming Tools"
+.IX Subsection "perlfaq3: Programming Tools"
+This section of the \s-1FAQ\s0 answers questions related to programmer tools and programming support.
+.IP "\(bu" 4
+How do I do (anything)?
+.IP "\(bu" 4
+How can I use Perl interactively?
+.IP "\(bu" 4
+How do I find which modules are installed on my system?
+.IP "\(bu" 4
+How do I debug my Perl programs?
+.IP "\(bu" 4
+How do I profile my Perl programs?
+.IP "\(bu" 4
+How do I cross-reference my Perl programs?
+.IP "\(bu" 4
+Is there a pretty-printer (formatter) for Perl?
+.IP "\(bu" 4
+Is there an \s-1IDE\s0 or Windows Perl Editor?
+.IP "\(bu" 4
+Where can I get Perl macros for vi?
+.IP "\(bu" 4
+Where can I get perl-mode or cperl-mode for emacs?
+.IP "\(bu" 4
+How can I use curses with Perl?
+.IP "\(bu" 4
+How can I write a \s-1GUI\s0 (X, Tk, Gtk, etc.) in Perl?
+.IP "\(bu" 4
+How can I make my Perl program run faster?
+.IP "\(bu" 4
+How can I make my Perl program take less memory?
+.IP "\(bu" 4
+Is it safe to return a reference to local or lexical data?
+.IP "\(bu" 4
+How can I free an array or hash so my program shrinks?
+.IP "\(bu" 4
+How can I make my \s-1CGI\s0 script more efficient?
+.IP "\(bu" 4
+How can I hide the source for my Perl program?
+.IP "\(bu" 4
+How can I compile my Perl program into byte code or C?
+.IP "\(bu" 4
+How can I get \f(CW\*(C`#!perl\*(C'\fR to work on [\s-1MS\-DOS,NT,...\s0]?
+.IP "\(bu" 4
+Can I write useful Perl programs on the command line?
+.IP "\(bu" 4
+Why don't Perl one-liners work on my DOS/Mac/VMS system?
+.IP "\(bu" 4
+Where can I learn about \s-1CGI\s0 or Web programming in Perl?
+.IP "\(bu" 4
+Where can I learn about object-oriented Perl programming?
+.IP "\(bu" 4
+Where can I learn about linking C with Perl?
+.IP "\(bu" 4
+I've read perlembed, perlguts, etc., but I can't embed perl in my C program; what am I doing wrong?
+.IP "\(bu" 4
+When I tried to run my script, I got this message. What does it mean?
+.IP "\(bu" 4
+What's MakeMaker?
+.SS "perlfaq4: Data Manipulation"
+.IX Subsection "perlfaq4: Data Manipulation"
+This section of the \s-1FAQ\s0 answers questions related to manipulating numbers, dates, strings, arrays, hashes, and miscellaneous data issues.
+.IP "\(bu" 4
+Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I should be getting (eg, 19.95)?
+.IP "\(bu" 4
+Why is \fBint()\fR broken?
+.IP "\(bu" 4
+Why isn't my octal data interpreted correctly?
+.IP "\(bu" 4
+Does Perl have a \fBround()\fR function? What about \fBceil()\fR and \fBfloor()\fR? Trig functions?
+.IP "\(bu" 4
+How do I convert between numeric representations/bases/radixes?
+.IP "\(bu" 4
+Why doesn't & work the way I want it to?
+.IP "\(bu" 4
+How do I multiply matrices?
+.IP "\(bu" 4
+How do I perform an operation on a series of integers?
+.IP "\(bu" 4
+How can I output Roman numerals?
+.IP "\(bu" 4
+Why aren't my random numbers random?
+.IP "\(bu" 4
+How do I get a random number between X and Y?
+.IP "\(bu" 4
+How do I find the day or week of the year?
+.IP "\(bu" 4
+How do I find the current century or millennium?
+.IP "\(bu" 4
+How can I compare two dates and find the difference?
+.IP "\(bu" 4
+How can I take a string and turn it into epoch seconds?
+.IP "\(bu" 4
+How can I find the Julian Day?
+.IP "\(bu" 4
+How do I find yesterday's date?
+.IP "\(bu" 4
+Does Perl have a Year 2000 or 2038 problem? Is Perl Y2K compliant?
+.IP "\(bu" 4
+How do I validate input?
+.IP "\(bu" 4
+How do I unescape a string?
+.IP "\(bu" 4
+How do I remove consecutive pairs of characters?
+.IP "\(bu" 4
+How do I expand function calls in a string?
+.IP "\(bu" 4
+How do I find matching/nesting anything?
+.IP "\(bu" 4
+How do I reverse a string?
+.IP "\(bu" 4
+How do I expand tabs in a string?
+.IP "\(bu" 4
+How do I reformat a paragraph?
+.IP "\(bu" 4
+How can I access or change N characters of a string?
+.IP "\(bu" 4
+How do I change the Nth occurrence of something?
+.IP "\(bu" 4
+How can I count the number of occurrences of a substring within a string?
+.IP "\(bu" 4
+How do I capitalize all the words on one line?
+.IP "\(bu" 4
+How can I split a [character]\-delimited string except when inside [character]?
+.IP "\(bu" 4
+How do I strip blank space from the beginning/end of a string?
+.IP "\(bu" 4
+How do I pad a string with blanks or pad a number with zeroes?
+.IP "\(bu" 4
+How do I extract selected columns from a string?
+.IP "\(bu" 4
+How do I find the soundex value of a string?
+.IP "\(bu" 4
+How can I expand variables in text strings?
+.IP "\(bu" 4
+Does Perl have anything like Ruby's #{} or Python's f string?
+.IP "\(bu" 4
+What's wrong with always quoting \*(L"$vars\*(R"?
+.IP "\(bu" 4
+Why don't my <<\s-1HERE\s0 documents work?
+.IP "\(bu" 4
+What is the difference between a list and an array?
+.IP "\(bu" 4
+What is the difference between \f(CW$array\fR[1] and \f(CW@array\fR[1]?
+.IP "\(bu" 4
+How can I remove duplicate elements from a list or array?
+.IP "\(bu" 4
+How can I tell whether a certain element is contained in a list or array?
+.IP "\(bu" 4
+How do I compute the difference of two arrays? How do I compute the intersection of two arrays?
+.IP "\(bu" 4
+How do I test whether two arrays or hashes are equal?
+.IP "\(bu" 4
+How do I find the first array element for which a condition is true?
+.IP "\(bu" 4
+How do I handle linked lists?
+.IP "\(bu" 4
+How do I handle circular lists?
+.IP "\(bu" 4
+How do I shuffle an array randomly?
+.IP "\(bu" 4
+How do I process/modify each element of an array?
+.IP "\(bu" 4
+How do I select a random element from an array?
+.IP "\(bu" 4
+How do I permute N elements of a list?
+.IP "\(bu" 4
+How do I sort an array by (anything)?
+.IP "\(bu" 4
+How do I manipulate arrays of bits?
+.IP "\(bu" 4
+Why does \fBdefined()\fR return true on empty arrays and hashes?
+.IP "\(bu" 4
+How do I process an entire hash?
+.IP "\(bu" 4
+How do I merge two hashes?
+.IP "\(bu" 4
+What happens if I add or remove keys from a hash while iterating over it?
+.IP "\(bu" 4
+How do I look up a hash element by value?
+.IP "\(bu" 4
+How can I know how many entries are in a hash?
+.IP "\(bu" 4
+How do I sort a hash (optionally by value instead of key)?
+.IP "\(bu" 4
+How can I always keep my hash sorted?
+.IP "\(bu" 4
+What's the difference between \*(L"delete\*(R" and \*(L"undef\*(R" with hashes?
+.IP "\(bu" 4
+Why don't my tied hashes make the defined/exists distinction?
+.IP "\(bu" 4
+How do I reset an \fBeach()\fR operation part-way through?
+.IP "\(bu" 4
+How can I get the unique keys from two hashes?
+.IP "\(bu" 4
+How can I store a multidimensional array in a \s-1DBM\s0 file?
+.IP "\(bu" 4
+How can I make my hash remember the order I put elements into it?
+.IP "\(bu" 4
+Why does passing a subroutine an undefined element in a hash create it?
+.IP "\(bu" 4
+How can I make the Perl equivalent of a C structure/\*(C+ class/hash or array of hashes or arrays?
+.IP "\(bu" 4
+How can I use a reference as a hash key?
+.IP "\(bu" 4
+How can I check if a key exists in a multilevel hash?
+.IP "\(bu" 4
+How can I prevent addition of unwanted keys into a hash?
+.IP "\(bu" 4
+How do I handle binary data correctly?
+.IP "\(bu" 4
+How do I determine whether a scalar is a number/whole/integer/float?
+.IP "\(bu" 4
+How do I keep persistent data across program calls?
+.IP "\(bu" 4
+How do I print out or copy a recursive data structure?
+.IP "\(bu" 4
+How do I define methods for every class/object?
+.IP "\(bu" 4
+How do I verify a credit card checksum?
+.IP "\(bu" 4
+How do I pack arrays of doubles or floats for \s-1XS\s0 code?
+.SS "perlfaq5: Files and Formats"
+.IX Subsection "perlfaq5: Files and Formats"
+This section deals with I/O and the \*(L"f\*(R" issues: filehandles, flushing, formats, and footers.
+.IP "\(bu" 4
+How do I flush/unbuffer an output filehandle? Why must I do this?
+.IP "\(bu" 4
+How do I change, delete, or insert a line in a file, or append to the beginning of a file?
+.IP "\(bu" 4
+How do I count the number of lines in a file?
+.IP "\(bu" 4
+How do I delete the last N lines from a file?
+.IP "\(bu" 4
+How can I use Perl's \f(CW\*(C`\-i\*(C'\fR option from within a program?
+.IP "\(bu" 4
+How can I copy a file?
+.IP "\(bu" 4
+How do I make a temporary file name?
+.IP "\(bu" 4
+How can I manipulate fixed-record-length files?
+.IP "\(bu" 4
+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?
+.IP "\(bu" 4
+How can I use a filehandle indirectly?
+.IP "\(bu" 4
+How can I open a filehandle to a string?
+.IP "\(bu" 4
+How can I set up a footer format to be used with \fBwrite()\fR?
+.IP "\(bu" 4
+How can I \fBwrite()\fR into a string?
+.IP "\(bu" 4
+How can I output my numbers with commas added?
+.IP "\(bu" 4
+How can I translate tildes (~) in a filename?
+.IP "\(bu" 4
+How come when I open a file read-write it wipes it out?
+.IP "\(bu" 4
+Why do I sometimes get an \*(L"Argument list too long\*(R" when I use <*>?
+.IP "\(bu" 4
+How can I open a file named with a leading \*(L">\*(R" or trailing blanks?
+.IP "\(bu" 4
+How can I reliably rename a file?
+.IP "\(bu" 4
+How can I lock a file?
+.IP "\(bu" 4
+Why can't I just open(\s-1FH, \*(L"\s0>file.lock\*(R")?
+.IP "\(bu" 4
+I still don't get locking. I just want to increment the number in the file. How can I do this?
+.IP "\(bu" 4
+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?
+.IP "\(bu" 4
+How do I randomly update a binary file?
+.IP "\(bu" 4
+How do I get a file's timestamp in perl?
+.IP "\(bu" 4
+How do I set a file's timestamp in perl?
+.IP "\(bu" 4
+How do I print to more than one file at once?
+.IP "\(bu" 4
+How can I read in an entire file all at once?
+.IP "\(bu" 4
+How can I read in a file by paragraphs?
+.IP "\(bu" 4
+How can I read a single character from a file? From the keyboard?
+.IP "\(bu" 4
+How can I tell whether there's a character waiting on a filehandle?
+.IP "\(bu" 4
+How do I do a \f(CW\*(C`tail \-f\*(C'\fR in perl?
+.IP "\(bu" 4
+How do I \fBdup()\fR a filehandle in Perl?
+.IP "\(bu" 4
+How do I close a file descriptor by number?
+.IP "\(bu" 4
+Why can't I use \*(L"C:\etemp\efoo\*(R" in \s-1DOS\s0 paths? Why doesn't `C:\etemp\efoo.exe` work?
+.IP "\(bu" 4
+Why doesn't glob(\*(L"*.*\*(R") get all the files?
+.IP "\(bu" 4
+Why does Perl let me delete read-only files? Why does \f(CW\*(C`\-i\*(C'\fR clobber protected files? Isn't this a bug in Perl?
+.IP "\(bu" 4
+How do I select a random line from a file?
+.IP "\(bu" 4
+Why do I get weird spaces when I print an array of lines?
+.IP "\(bu" 4
+How do I traverse a directory tree?
+.IP "\(bu" 4
+How do I delete a directory tree?
+.IP "\(bu" 4
+How do I copy an entire directory?
+.SS "perlfaq6: Regular Expressions"
+.IX Subsection "perlfaq6: Regular Expressions"
+This section is surprisingly small because the rest of the \s-1FAQ\s0 is littered with answers involving regular expressions. For example, decoding a \s-1URL\s0 and checking whether something is a number can be handled with regular expressions, but those answers are found elsewhere in this document (in perlfaq9 : \*(L"How do I decode or create those %\-encodings on the web\*(R" and perlfaq4 : \*(L"How do I determine whether a scalar is a number/whole/integer/float\*(R", to be precise).
+.IP "\(bu" 4
+How can I hope to use regular expressions without creating illegible and unmaintainable code?
+.IP "\(bu" 4
+I'm having trouble matching over more than one line. What's wrong?
+.IP "\(bu" 4
+How can I pull out lines between two patterns that are themselves on different lines?
+.IP "\(bu" 4
+How do I match \s-1XML, HTML,\s0 or other nasty, ugly things with a regex?
+.IP "\(bu" 4
+I put a regular expression into $/ but it didn't work. What's wrong?
+.IP "\(bu" 4
+How do I substitute case-insensitively on the \s-1LHS\s0 while preserving case on the \s-1RHS\s0?
+.IP "\(bu" 4
+How can I make \f(CW\*(C`\ew\*(C'\fR match national character sets?
+.IP "\(bu" 4
+How can I match a locale-smart version of \f(CW\*(C`/[a\-zA\-Z]/\*(C'\fR ?
+.IP "\(bu" 4
+How can I quote a variable to use in a regex?
+.IP "\(bu" 4
+What is \f(CW\*(C`/o\*(C'\fR really for?
+.IP "\(bu" 4
+How do I use a regular expression to strip C\-style comments from a file?
+.IP "\(bu" 4
+Can I use Perl regular expressions to match balanced text?
+.IP "\(bu" 4
+What does it mean that regexes are greedy? How can I get around it?
+.IP "\(bu" 4
+How do I process each word on each line?
+.IP "\(bu" 4
+How can I print out a word-frequency or line-frequency summary?
+.IP "\(bu" 4
+How can I do approximate matching?
+.IP "\(bu" 4
+How do I efficiently match many regular expressions at once?
+.IP "\(bu" 4
+Why don't word-boundary searches with \f(CW\*(C`\eb\*(C'\fR work for me?
+.IP "\(bu" 4
+Why does using $&, $`, or $' slow my program down?
+.IP "\(bu" 4
+What good is \f(CW\*(C`\eG\*(C'\fR in a regular expression?
+.IP "\(bu" 4
+Are Perl regexes DFAs or NFAs? Are they \s-1POSIX\s0 compliant?
+.IP "\(bu" 4
+What's wrong with using grep in a void context?
+.IP "\(bu" 4
+How can I match strings with multibyte characters?
+.IP "\(bu" 4
+How do I match a regular expression that's in a variable?
+.SS "perlfaq7: General Perl Language Issues"
+.IX Subsection "perlfaq7: General Perl Language Issues"
+This section deals with general Perl language issues that don't clearly fit into any of the other sections.
+.IP "\(bu" 4
+Can I get a BNF/yacc/RE for the Perl language?
+.IP "\(bu" 4
+What are all these $@%&* punctuation signs, and how do I know when to use them?
+.IP "\(bu" 4
+Do I always/never have to quote my strings or use semicolons and commas?
+.IP "\(bu" 4
+How do I skip some return values?
+.IP "\(bu" 4
+How do I temporarily block warnings?
+.IP "\(bu" 4
+What's an extension?
+.IP "\(bu" 4
+Why do Perl operators have different precedence than C operators?
+.IP "\(bu" 4
+How do I declare/create a structure?
+.IP "\(bu" 4
+How do I create a module?
+.IP "\(bu" 4
+How do I adopt or take over a module already on \s-1CPAN\s0?
+.IP "\(bu" 4
+How do I create a class?
+.IP "\(bu" 4
+How can I tell if a variable is tainted?
+.IP "\(bu" 4
+What's a closure?
+.IP "\(bu" 4
+What is variable suicide and how can I prevent it?
+.IP "\(bu" 4
+How can I pass/return a {Function, FileHandle, Array, Hash, Method, Regex}?
+.IP "\(bu" 4
+How do I create a static variable?
+.IP "\(bu" 4
+What's the difference between dynamic and lexical (static) scoping? Between \fBlocal()\fR and \fBmy()\fR?
+.IP "\(bu" 4
+How can I access a dynamic variable while a similarly named lexical is in scope?
+.IP "\(bu" 4
+What's the difference between deep and shallow binding?
+.IP "\(bu" 4
+Why doesn't \*(L"my($foo) = <$fh>;\*(R" work right?
+.IP "\(bu" 4
+How do I redefine a builtin function, operator, or method?
+.IP "\(bu" 4
+What's the difference between calling a function as &foo and \fBfoo()\fR?
+.IP "\(bu" 4
+How do I create a switch or case statement?
+.IP "\(bu" 4
+How can I catch accesses to undefined variables, functions, or methods?
+.IP "\(bu" 4
+Why can't a method included in this same file be found?
+.IP "\(bu" 4
+How can I find out my current or calling package?
+.IP "\(bu" 4
+How can I comment out a large block of Perl code?
+.IP "\(bu" 4
+How do I clear a package?
+.IP "\(bu" 4
+How can I use a variable as a variable name?
+.IP "\(bu" 4
+What does \*(L"bad interpreter\*(R" mean?
+.IP "\(bu" 4
+Do I need to recompile \s-1XS\s0 modules when there is a change in the C library?
+.SS "perlfaq8: System Interaction"
+.IX Subsection "perlfaq8: System Interaction"
+This section of the Perl \s-1FAQ\s0 covers questions involving operating system interaction. Topics include interprocess communication (\s-1IPC\s0), control over the user-interface (keyboard, screen and pointing devices), and most anything else not related to data manipulation.
+.IP "\(bu" 4
+How do I find out which operating system I'm running under?
+.IP "\(bu" 4
+How come \fBexec()\fR doesn't return?
+.IP "\(bu" 4
+How do I do fancy stuff with the keyboard/screen/mouse?
+.IP "\(bu" 4
+How do I print something out in color?
+.IP "\(bu" 4
+How do I read just one key without waiting for a return key?
+.IP "\(bu" 4
+How do I check whether input is ready on the keyboard?
+.IP "\(bu" 4
+How do I clear the screen?
+.IP "\(bu" 4
+How do I get the screen size?
+.IP "\(bu" 4
+How do I ask the user for a password?
+.IP "\(bu" 4
+How do I read and write the serial port?
+.IP "\(bu" 4
+How do I decode encrypted password files?
+.IP "\(bu" 4
+How do I start a process in the background?
+.IP "\(bu" 4
+How do I trap control characters/signals?
+.IP "\(bu" 4
+How do I modify the shadow password file on a Unix system?
+.IP "\(bu" 4
+How do I set the time and date?
+.IP "\(bu" 4
+How can I \fBsleep()\fR or \fBalarm()\fR for under a second?
+.IP "\(bu" 4
+How can I measure time under a second?
+.IP "\(bu" 4
+How can I do an \fBatexit()\fR or \fBsetjmp()\fR/\fBlongjmp()\fR? (Exception handling)
+.IP "\(bu" 4
+Why doesn't my sockets program work under System V (Solaris)? What does the error message \*(L"Protocol not supported\*(R" mean?
+.IP "\(bu" 4
+How can I call my system's unique C functions from Perl?
+.IP "\(bu" 4
+Where do I get the include files to do \fBioctl()\fR or \fBsyscall()\fR?
+.IP "\(bu" 4
+Why do setuid perl scripts complain about kernel problems?
+.IP "\(bu" 4
+How can I open a pipe both to and from a command?
+.IP "\(bu" 4
+Why can't I get the output of a command with \fBsystem()\fR?
+.IP "\(bu" 4
+How can I capture \s-1STDERR\s0 from an external command?
+.IP "\(bu" 4
+Why doesn't \fBopen()\fR return an error when a pipe open fails?
+.IP "\(bu" 4
+What's wrong with using backticks in a void context?
+.IP "\(bu" 4
+How can I call backticks without shell processing?
+.IP "\(bu" 4
+Why can't my script read from \s-1STDIN\s0 after I gave it \s-1EOF\s0 (^D on Unix, ^Z on MS-DOS)?
+.IP "\(bu" 4
+How can I convert my shell script to perl?
+.IP "\(bu" 4
+Can I use perl to run a telnet or ftp session?
+.IP "\(bu" 4
+How can I write expect in Perl?
+.IP "\(bu" 4
+Is there a way to hide perl's command line from programs such as \*(L"ps\*(R"?
+.IP "\(bu" 4
+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?
+.IP "\(bu" 4
+How do I close a process's filehandle without waiting for it to complete?
+.IP "\(bu" 4
+How do I fork a daemon process?
+.IP "\(bu" 4
+How do I find out if I'm running interactively or not?
+.IP "\(bu" 4
+How do I timeout a slow event?
+.IP "\(bu" 4
+How do I set \s-1CPU\s0 limits?
+.IP "\(bu" 4
+How do I avoid zombies on a Unix system?
+.IP "\(bu" 4
+How do I use an \s-1SQL\s0 database?
+.IP "\(bu" 4
+How do I make a \fBsystem()\fR exit on control-C?
+.IP "\(bu" 4
+How do I open a file without blocking?
+.IP "\(bu" 4
+How do I tell the difference between errors from the shell and perl?
+.IP "\(bu" 4
+How do I install a module from \s-1CPAN\s0?
+.IP "\(bu" 4
+What's the difference between require and use?
+.IP "\(bu" 4
+How do I keep my own module/library directory?
+.IP "\(bu" 4
+How do I add the directory my program lives in to the module/library search path?
+.IP "\(bu" 4
+How do I add a directory to my include path (@INC) at runtime?
+.IP "\(bu" 4
+Where are modules installed?
+.IP "\(bu" 4
+What is socket.ph and where do I get it?
+.SS "perlfaq9: Web, Email and Networking"
+.IX Subsection "perlfaq9: Web, Email and Networking"
+This section deals with questions related to running web sites, sending and receiving email as well as general networking.
+.IP "\(bu" 4
+Should I use a web framework?
+.IP "\(bu" 4
+Which web framework should I use?
+.IP "\(bu" 4
+What is Plack and \s-1PSGI\s0?
+.IP "\(bu" 4
+How do I remove \s-1HTML\s0 from a string?
+.IP "\(bu" 4
+How do I extract URLs?
+.IP "\(bu" 4
+How do I fetch an \s-1HTML\s0 file?
+.IP "\(bu" 4
+How do I automate an \s-1HTML\s0 form submission?
+.IP "\(bu" 4
+How do I decode or create those %\-encodings on the web?
+.IP "\(bu" 4
+How do I redirect to another page?
+.IP "\(bu" 4
+How do I put a password on my web pages?
+.IP "\(bu" 4
+How do I make sure users can't enter values into a form that causes my \s-1CGI\s0 script to do bad things?
+.IP "\(bu" 4
+How do I parse a mail header?
+.IP "\(bu" 4
+How do I check a valid mail address?
+.IP "\(bu" 4
+How do I decode a \s-1MIME/BASE64\s0 string?
+.IP "\(bu" 4
+How do I find the user's mail address?
+.IP "\(bu" 4
+How do I send email?
+.IP "\(bu" 4
+How do I use \s-1MIME\s0 to make an attachment to a mail message?
+.IP "\(bu" 4
+How do I read email?
+.IP "\(bu" 4
+How do I find out my hostname, domainname, or \s-1IP\s0 address?
+.IP "\(bu" 4
+How do I fetch/put an (S)FTP file?
+.IP "\(bu" 4
+How can I do \s-1RPC\s0 in Perl?
+.SH "CREDITS"
+.IX Header "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.
+.SH "AUTHOR AND COPYRIGHT"
+.IX Header "AUTHOR AND COPYRIGHT"
+Tom Christiansen wrote the original version of this document.
+brian d foy \f(CW\*(C`<bdfoy@cpan.org>\*(C'\fR wrote this version. See the
+individual perlfaq documents for additional copyright information.
+.PP
+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).