From: Robin Barker Date: Fri, 5 Jan 2001 18:51:20 +0000 (+0000) Subject: format and rewording in perlfaq.pod X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=40d4dc3e90c1c3b3062669c126a23ad83b2ca878;p=p5sagit%2Fp5-mst-13.2.git format and rewording in perlfaq.pod Message-Id: <200101051851.SAA03310@tempest.npl.co.uk> p4raw-id: //depot/perl@8339 --- diff --git a/pod/perlfaq.pod b/pod/perlfaq.pod index f587a8d..bc29c69 100644 --- a/pod/perlfaq.pod +++ b/pod/perlfaq.pod @@ -4,708 +4,1303 @@ perlfaq - frequently asked questions about Perl ($Date: 1999/05/23 20:38:02 $) =head1 DESCRIPTION -This document is structured into the following sections: +The perlfaq is structured into the following documents: -=over 4 -=item perlfaq: Structural overview of the FAQ. +=head2 perlfaq: Structural overview of the FAQ. This document. -=item L: General Questions About Perl +=head2 L: General Questions About Perl Very general, high-level information about Perl. =over 4 -=item * What is Perl? +=item * + +What is Perl? + +=item * + +Who supports Perl? Who develops it? Why is it free? + +=item * + +Which version of Perl should I use? + +=item * + +What are perl4 and perl5? + +=item * + +What is perl6? -=item * Who supports Perl? Who develops it? Why is it free? +=item * -=item * Which version of Perl should I use? +How stable is Perl? -=item * What are perl4 and perl5? +=item * -=item * What is perl6? +Is Perl difficult to learn? -=item * How stable is Perl? +=item * -=item * Is Perl difficult to learn? +How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl? -=item * How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl? +=item * -=item * Can I do [task] in Perl? +Can I do [task] in Perl? -=item * When shouldn't I program in Perl? +=item * -=item * What's the difference between "perl" and "Perl"? +When shouldn't I program in Perl? -=item * Is it a Perl program or a Perl script? +=item * -=item * What is a JAPH? +What's the difference between "perl" and "Perl"? -=item * Where can I get a list of Larry Wall witticisms? +=item * -=item * How can I convince my sysadmin/supervisor/employees to use version 5/5.005/Perl instead of some other language? +Is it a Perl program or a Perl script? + +=item * + +What is a JAPH? + +=item * + +Where can I get a list of Larry Wall witticisms? + +=item * + +How can I convince my sysadmin/supervisor/employees to use version 5/5.005/Perl instead of some other language? =back -=item L: Obtaining and Learning about Perl +=head2 L: Obtaining and Learning about Perl Where to find source and documentation to Perl, support, and related matters. =over 4 -=item * What machines support Perl? Where do I get it? +=item * + +What machines support Perl? Where do I get it? + +=item * + +How can I get a binary version of Perl? -=item * How can I get a binary version of Perl? +=item * -=item * I don't have a C compiler on my system. How can I compile perl? +I don't have a C compiler on my system. How can I compile perl? -=item * I copied the Perl binary from one machine to another, but scripts don't work. +=item * -=item * I grabbed the sources and tried to compile but gdbm/dynamic loading/malloc/linking/... failed. How do I make it work? +I copied the Perl binary from one machine to another, but scripts don't work. -=item * What modules and extensions are available for Perl? What is CPAN? What does CPAN/src/... mean? +=item * -=item * Is there an ISO or ANSI certified version of Perl? +I grabbed the sources and tried to compile but gdbm/dynamic loading/malloc/linking/... failed. How do I make it work? -=item * Where can I get information on Perl? +=item * -=item * What are the Perl newsgroups on Usenet? Where do I post questions? +What modules and extensions are available for Perl? What is CPAN? What does CPAN/src/... mean? -=item * Where should I post source code? +=item * -=item * Perl Books +Is there an ISO or ANSI certified version of Perl? -=item * Perl in Magazines +=item * -=item * Perl on the Net: FTP and WWW Access +Where can I get information on Perl? -=item * What mailing lists are there for Perl? +=item * -=item * Archives of comp.lang.perl.misc +What are the Perl newsgroups on Usenet? Where do I post questions? -=item * Where can I buy a commercial version of Perl? +=item * -=item * Where do I send bug reports? +Where should I post source code? -=item * What is perl.com? Perl Mongers? pm.org? perl.org? +=item * + +Perl Books + +=item * + +Perl in Magazines + +=item * + +Perl on the Net: FTP and WWW Access + +=item * + +What mailing lists are there for Perl? + +=item * + +Archives of comp.lang.perl.misc + +=item * + +Where can I buy a commercial version of Perl? + +=item * + +Where do I send bug reports? + +=item * + +What is perl.com? Perl Mongers? pm.org? perl.org? =back -=item L: Programming Tools +=head2 L: Programming Tools Programmer tools and programming support. =over 4 -=item * How do I do (anything)? +=item * + +How do I do (anything)? + +=item * + +How can I use Perl interactively? + +=item * -=item * How can I use Perl interactively? +Is there a Perl shell? -=item * Is there a Perl shell? +=item * -=item * How do I debug my Perl programs? +How do I debug my Perl programs? -=item * How do I profile my Perl programs? +=item * -=item * How do I cross-reference my Perl programs? +How do I profile my Perl programs? -=item * Is there a pretty-printer (formatter) for Perl? +=item * -=item * Is there a ctags for Perl? +How do I cross-reference my Perl programs? -=item * Is there an IDE or Windows Perl Editor? +=item * -=item * Where can I get Perl macros for vi? +Is there a pretty-printer (formatter) for Perl? -=item * Where can I get perl-mode for emacs? +=item * -=item * How can I use curses with Perl? +Is there a ctags for Perl? -=item * How can I use X or Tk with Perl? +=item * -=item * How can I generate simple menus without using CGI or Tk? +Is there an IDE or Windows Perl Editor? -=item * What is undump? +=item * -=item * How can I make my Perl program run faster? +Where can I get Perl macros for vi? -=item * How can I make my Perl program take less memory? +=item * -=item * Is it unsafe to return a pointer to local data? +Where can I get perl-mode for emacs? -=item * How can I free an array or hash so my program shrinks? +=item * -=item * How can I make my CGI script more efficient? +How can I use curses with Perl? -=item * How can I hide the source for my Perl program? +=item * -=item * How can I compile my Perl program into byte code or C? +How can I use X or Tk with Perl? -=item * How can I compile Perl into Java? +=item * -=item * How can I get C<#!perl> to work on [MS-DOS,NT,...]? +How can I generate simple menus without using CGI or Tk? -=item * Can I write useful Perl programs on the command line? +=item * -=item * Why don't Perl one-liners work on my DOS/Mac/VMS system? +What is undump? -=item * Where can I learn about CGI or Web programming in Perl? +=item * -=item * Where can I learn about object-oriented Perl programming? +How can I make my Perl program run faster? -=item * Where can I learn about linking C with Perl? [h2xs, xsubpp] +=item * -=item * I've read perlembed, perlguts, etc., but I can't embed perl in +How can I make my Perl program take less memory? + +=item * + +Is it unsafe to return a pointer to local data? + +=item * + +How can I free an array or hash so my program shrinks? + +=item * + +How can I make my CGI script more efficient? + +=item * + +How can I hide the source for my Perl program? + +=item * + +How can I compile my Perl program into byte code or C? + +=item * + +How can I compile Perl into Java? + +=item * + +How can I get C<#!perl> to work on [MS-DOS,NT,...]? + +=item * + +Can I write useful Perl programs on the command line? + +=item * + +Why don't Perl one-liners work on my DOS/Mac/VMS system? + +=item * + +Where can I learn about CGI or Web programming in Perl? + +=item * + +Where can I learn about object-oriented Perl programming? + +=item * + +Where can I learn about linking C with Perl? [h2xs, xsubpp] + +=item * + +I've read perlembed, perlguts, etc., but I can't embed perl in my C program; what am I doing wrong? -=item * When I tried to run my script, I got this message. What does it +=item * + +When I tried to run my script, I got this message. What does it mean? -=item * What's MakeMaker? +=item * + +What's MakeMaker? =back -=item L: Data Manipulation +=head2 L: Data Manipulation Manipulating numbers, dates, strings, arrays, hashes, and miscellaneous data issues. =over 4 -=item * Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I should be getting (eg, 19.95)? +=item * + +Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I should be getting (eg, 19.95)? + +=item * + +Why isn't my octal data interpreted correctly? + +=item * + +Does Perl have a round() function? What about ceil() and floor()? Trig functions? + +=item * + +How do I convert bits into ints? + +=item * + +Why doesn't & work the way I want it to? -=item * Why isn't my octal data interpreted correctly? +=item * -=item * Does Perl have a round() function? What about ceil() and floor()? Trig functions? +How do I multiply matrices? -=item * How do I convert bits into ints? +=item * -=item * Why doesn't & work the way I want it to? +How do I perform an operation on a series of integers? -=item * How do I multiply matrices? +=item * -=item * How do I perform an operation on a series of integers? +How can I output Roman numerals? -=item * How can I output Roman numerals? +=item * -=item * Why aren't my random numbers random? +Why aren't my random numbers random? -=item * How do I find the week-of-the-year/day-of-the-year? +=item * -=item * How do I find the current century or millennium? +How do I find the week-of-the-year/day-of-the-year? -=item * How can I compare two dates and find the difference? +=item * -=item * How can I take a string and turn it into epoch seconds? +How do I find the current century or millennium? -=item * How can I find the Julian Day? +=item * -=item * How do I find yesterday's date? +How can I compare two dates and find the difference? -=item * Does Perl have a Year 2000 problem? Is Perl Y2K compliant? +=item * -=item * How do I validate input? +How can I take a string and turn it into epoch seconds? -=item * How do I unescape a string? +=item * -=item * How do I remove consecutive pairs of characters? +How can I find the Julian Day? -=item * How do I expand function calls in a string? +=item * -=item * How do I find matching/nesting anything? +How do I find yesterday's date? -=item * How do I reverse a string? +=item * -=item * How do I expand tabs in a string? +Does Perl have a Year 2000 problem? Is Perl Y2K compliant? -=item * How do I reformat a paragraph? +=item * -=item * How can I access/change the first N letters of a string? +How do I validate input? -=item * How do I change the Nth occurrence of something? +=item * -=item * How can I count the number of occurrences of a substring within a string? +How do I unescape a string? -=item * How do I capitalize all the words on one line? +=item * -=item * How can I split a [character] delimited string except when inside +How do I remove consecutive pairs of characters? + +=item * + +How do I expand function calls in a string? + +=item * + +How do I find matching/nesting anything? + +=item * + +How do I reverse a string? + +=item * + +How do I expand tabs in a string? + +=item * + +How do I reformat a paragraph? + +=item * + +How can I access/change the first N letters of a string? + +=item * + +How do I change the Nth occurrence of something? + +=item * + +How can I count the number of occurrences of a substring within a string? + +=item * + +How do I capitalize all the words on one line? + +=item * + +How can I split a [character] delimited string except when inside [character]? (Comma-separated files) -=item * How do I strip blank space from the beginning/end of a string? +=item * + +How do I strip blank space from the beginning/end of a string? + +=item * + +How do I pad a string with blanks or pad a number with zeroes? + +=item * + +How do I extract selected columns from a string? + +=item * + +How do I find the soundex value of a string? + +=item * + +How can I expand variables in text strings? + +=item * + +What's wrong with always quoting "$vars"? + +=item * + +Why don't my <: Files and Formats +=head2 L: Files and Formats I/O and the "f" issues: filehandles, flushing, formats and footers. =over 4 -=item * How do I flush/unbuffer an output filehandle? Why must I do this? +=item * + +How do I flush/unbuffer an output filehandle? Why must I do this? + +=item * + +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? + +=item * + +How do I count the number of lines in a file? + +=item * + +How do I make a temporary file name? + +=item * + +How can I manipulate fixed-record-length files? + +=item * -=item * 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? +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? -=item * How do I count the number of lines in a file? +=item * -=item * How do I make a temporary file name? +How can I use a filehandle indirectly? -=item * How can I manipulate fixed-record-length files? +=item * -=item * 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? +How can I set up a footer format to be used with write()? -=item * How can I use a filehandle indirectly? +=item * -=item * How can I set up a footer format to be used with write()? +How can I write() into a string? -=item * How can I write() into a string? +=item * -=item * How can I output my numbers with commas added? +How can I output my numbers with commas added? -=item * How can I translate tildes (~) in a filename? +=item * -=item * How come when I open a file read-write it wipes it out? +How can I translate tildes (~) in a filename? -=item * Why do I sometimes get an "Argument list too long" when I use <*>? +=item * -=item * Is there a leak/bug in glob()? +How come when I open a file read-write it wipes it out? -=item * How can I open a file with a leading ">" or trailing blanks? +=item * -=item * How can I reliably rename a file? +Why do I sometimes get an "Argument list too long" when I use <*>? -=item * How can I lock a file? +=item * -=item * Why can't I just open(FH, ">file.lock")? +Is there a leak/bug in glob()? -=item * I still don't get locking. I just want to increment the number in the file. How can I do this? +=item * -=item * How do I randomly update a binary file? +How can I open a file with a leading ">" or trailing blanks? -=item * How do I get a file's timestamp in perl? +=item * -=item * How do I set a file's timestamp in perl? +How can I reliably rename a file? -=item * How do I print to more than one file at once? +=item * -=item * How can I read in an entire file all at once? +How can I lock a file? -=item * How can I read in a file by paragraphs? +=item * -=item * How can I read a single character from a file? From the keyboard? +Why can't I just open(FH, ">file.lock")? -=item * How can I tell whether there's a character waiting on a filehandle? +=item * -=item * How do I do a C in perl? +I still don't get locking. I just want to increment the number in the file. How can I do this? -=item * How do I dup() a filehandle in Perl? +=item * -=item * How do I close a file descriptor by number? +How do I randomly update a binary file? -=item * Why can't I use "C:\temp\foo" in DOS paths? What doesn't `C:\temp\foo.exe` work? +=item * -=item * Why doesn't glob("*.*") get all the files? +How do I get a file's timestamp in perl? -=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 * -=item * How do I select a random line from a file? +How do I set a file's timestamp in perl? -=item * Why do I get weird spaces when I print an array of lines? +=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 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? What 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? =back -=item L: Regexps +=head2 L: Regexps Pattern matching and regular expressions. =over 4 -=item * How can I hope to use regular expressions without creating illegible and unmaintainable code? +=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 * + +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? -=item * I'm having trouble matching over more than one line. What's wrong? +=item * -=item * How can I pull out lines between two patterns that are themselves on different lines? +How can I quote a variable to use in a regex? -=item * I put a regular expression into $/ but it didn't work. What's wrong? +=item * -=item * How do I substitute case insensitively on the LHS while preserving case on the RHS? +What is C really for? -=item * How can I make C<\w> match national character sets? +=item * -=item * How can I match a locale-smart version of C? +How do I use a regular expression to strip C style comments from a file? -=item * How can I quote a variable to use in a regex? +=item * -=item * What is C really for? +Can I use Perl regular expressions to match balanced text? -=item * How do I use a regular expression to strip C style comments from a file? +=item * -=item * Can I use Perl regular expressions to match balanced text? +What does it mean that regexes are greedy? How can I get around it? -=item * What does it mean that regexes are greedy? How can I get around it? +=item * -=item * How do I process each word on each line? +How do I process each word on each line? -=item * How can I print out a word-frequency or line-frequency summary? +=item * -=item * How can I do approximate matching? +How can I print out a word-frequency or line-frequency summary? -=item * How do I efficiently match many regular expressions at once? +=item * -=item * Why don't word-boundary searches with C<\b> work for me? +How can I do approximate matching? -=item * Why does using $&, $`, or $' slow my program down? +=item * -=item * What good is C<\G> in a regular expression? +How do I efficiently match many regular expressions at once? -=item * Are Perl regexes DFAs or NFAs? Are they POSIX compliant? +=item * -=item * What's wrong with using grep or map in a void context? +Why don't word-boundary searches with C<\b> work for me? -=item * How can I match strings with multibyte characters? +=item * -=item * How do I match a pattern that is supplied by the user? +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 or map in a void context? + +=item * + +How can I match strings with multibyte characters? + +=item * + +How do I match a pattern that is supplied by the user? =back -=item L: General Perl Language Issues +=head2 L: General Perl Language Issues 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 * + +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 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 * What are all these $@%&* punctuation signs, and how do I know when to use them? +=item * -=item * Do I always/never have to quote my strings or use semicolons and commas? +How do I create a static variable? -=item * How do I skip some return values? +=item * -=item * How do I temporarily block warnings? +What's the difference between dynamic and lexical (static) scoping? Between local() and my()? -=item * What's an extension? +=item * -=item * Why do Perl operators have different precedence than C operators? +How can I access a dynamic variable while a similarly named lexical is in scope? -=item * How do I declare/create a structure? +=item * -=item * How do I create a module? +What's the difference between deep and shallow binding? -=item * How do I create a class? +=item * -=item * How can I tell if a variable is tainted? +Why doesn't "my($foo) = ;" work right? -=item * What's a closure? +=item * -=item * What is variable suicide and how can I prevent it? +How do I redefine a builtin function, operator, or method? -=item * How can I pass/return a {Function, FileHandle, Array, Hash, Method, Regex}? +=item * -=item * How do I create a static variable? +What's the difference between calling a function as &foo and foo()? -=item * What's the difference between dynamic and lexical (static) scoping? Between local() and my()? +=item * -=item * How can I access a dynamic variable while a similarly named lexical is in scope? +How do I create a switch or case statement? -=item * What's the difference between deep and shallow binding? +=item * -=item * Why doesn't "my($foo) = ;" work right? +How can I catch accesses to undefined variables/functions/methods? -=item * How do I redefine a builtin function, operator, or method? +=item * -=item * What's the difference between calling a function as &foo and foo()? +Why can't a method included in this same file be found? -=item * How do I create a switch or case statement? +=item * -=item * How can I catch accesses to undefined variables/functions/methods? +How can I find out my current package? -=item * Why can't a method included in this same file be found? +=item * -=item * How can I find out my current package? +How can I comment out a large block of perl code? -=item * How can I comment out a large block of perl code? +=item * -=item * How do I clear a package? +How do I clear a package? -=item * How can I use a variable as a variable name? +=item * + +How can I use a variable as a variable name? =back -=item L: System Interaction +=head2 L: System Interaction Interprocess communication (IPC), control over the user-interface (keyboard, screen and pointing devices). =over 4 -=item * How do I find out which operating system I'm running under? +=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 come exec() doesn't return? +=item * -=item * How do I do fancy stuff with the keyboard/screen/mouse? +How can I call my system's unique C functions from Perl? -=item * How do I print something out in color? +=item * -=item * How do I read just one key without waiting for a return key? +Where do I get the include files to do ioctl() or syscall()? -=item * How do I check whether input is ready on the keyboard? +=item * -=item * How do I clear the screen? +Why do setuid perl scripts complain about kernel problems? -=item * How do I get the screen size? +=item * -=item * How do I ask the user for a password? +How can I open a pipe both to and from a command? -=item * How do I read and write the serial port? +=item * -=item * How do I decode encrypted password files? +Why can't I get the output of a command with system()? -=item * How do I start a process in the background? +=item * -=item * How do I trap control characters/signals? +How can I capture STDERR from an external command? -=item * How do I modify the shadow password file on a Unix system? +=item * -=item * How do I set the time and date? +Why doesn't open() return an error when a pipe open fails? -=item * How can I sleep() or alarm() for under a second? +=item * -=item * How can I measure time under a second? +What's wrong with using backticks in a void context? -=item * How can I do an atexit() or setjmp()/longjmp()? (Exception handling) +=item * -=item * Why doesn't my sockets program work under System V (Solaris)? What does the error message "Protocol not supported" mean? +How can I call backticks without shell processing? -=item * How can I call my system's unique C functions from Perl? +=item * -=item * Where do I get the include files to do ioctl() or syscall()? +Why can't my script read from STDIN after I gave it EOF (^D on Unix, ^Z on MS-DOS)? -=item * Why do setuid perl scripts complain about kernel problems? +=item * -=item * How can I open a pipe both to and from a command? +How can I convert my shell script to perl? -=item * Why can't I get the output of a command with system()? +=item * -=item * How can I capture STDERR from an external command? +Can I use perl to run a telnet or ftp session? -=item * Why doesn't open() return an error when a pipe open fails? +=item * -=item * What's wrong with using backticks in a void context? +How can I write expect in Perl? -=item * How can I call backticks without shell processing? +=item * -=item * Why can't my script read from STDIN after I gave it EOF (^D on Unix, ^Z on MS-DOS)? +Is there a way to hide perl's command line from programs such as "ps"? -=item * How can I convert my shell script to perl? +=item * -=item * Can I use perl to run a telnet or ftp session? +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 can I write expect in Perl? +=item * -=item * Is there a way to hide perl's command line from programs such as "ps"? +How do I close a process's filehandle without waiting for it to complete? -=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 * -=item * How do I close a process's filehandle without waiting for it to complete? +How do I fork a daemon process? -=item * How do I fork a daemon process? +=item * -=item * How do I find out if I'm running interactively or not? +How do I find out if I'm running interactively or not? -=item * How do I timeout a slow event? +=item * -=item * How do I set CPU limits? +How do I timeout a slow event? -=item * How do I avoid zombies on a Unix system? +=item * -=item * How do I use an SQL database? +How do I set CPU limits? -=item * How do I make a system() exit on control-C? +=item * -=item * How do I open a file without blocking? +How do I avoid zombies on a Unix system? -=item * How do I install a module from CPAN? +=item * -=item * What's the difference between require and use? +How do I use an SQL database? -=item * How do I keep my own module/library directory? +=item * -=item * How do I add the directory my program lives in to the module/library search path? +How do I make a system() exit on control-C? -=item * How do I add a directory to my include path at runtime? +=item * -=item * What is socket.ph and where do I get it? +How do I open a file without blocking? + +=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 at runtime? + +=item * + +What is socket.ph and where do I get it? =back -=item L: Networking +=head2 L: Networking Networking, the Internet, and a few on the web. =over 4 -=item * My CGI script runs from the command line but not the browser. (500 Server Error) +=item * -=item * How can I get better error messages from a CGI program? +My CGI script runs from the command line but not the browser. (500 Server Error) -=item * How do I remove HTML from a string? +=item * -=item * How do I extract URLs? +How can I get better error messages from a CGI program? -=item * How do I download a file from the user's machine? How do I open a file on another machine? +=item * -=item * How do I make a pop-up menu in HTML? +How do I remove HTML from a string? -=item * How do I fetch an HTML file? +=item * -=item * How do I automate an HTML form submission? +How do I extract URLs? -=item * How do I decode or create those %-encodings on the web? +=item * -=item * How do I redirect to another page? +How do I download a file from the user's machine? How do I open a file on another machine? -=item * How do I put a password on my web pages? +=item * -=item * How do I edit my .htpasswd and .htgroup files with Perl? +How do I make a pop-up menu in HTML? -=item * How do I make sure users can't enter values into a form that cause my CGI script to do bad things? +=item * -=item * How do I parse a mail header? +How do I fetch an HTML file? -=item * How do I decode a CGI form? +=item * -=item * How do I check a valid mail address? +How do I automate an HTML form submission? -=item * How do I decode a MIME/BASE64 string? +=item * -=item * How do I return the user's mail address? +How do I decode or create those %-encodings on the web? -=item * How do I send mail? +=item * -=item * How do I read mail? +How do I redirect to another page? -=item * How do I find out my hostname/domainname/IP address? +=item * -=item * How do I fetch a news article or the active newsgroups? +How do I put a password on my web pages? -=item * How do I fetch/put an FTP file? +=item * -=item * How can I do RPC in Perl? +How do I edit my .htpasswd and .htgroup files with Perl? -=back +=item * + +How do I make sure users can't enter values into a form that cause my CGI script to do bad things? + +=item * + +How do I parse a mail header? + +=item * + +How do I decode a CGI form? + +=item * +How do I check a valid mail address? + +=item * + +How do I decode a MIME/BASE64 string? + +=item * + +How do I return the user's mail address? + +=item * + +How do I send mail? + +=item * + +How do I read mail? + +=item * + +How do I find out my hostname/domainname/IP address? + +=item * + +How do I fetch a news article or the active newsgroups? + +=item * + +How do I fetch/put an FTP file? + +=item * + +How can I do RPC in Perl? =back -=head2 Where to get this document + +=head1 About the perlfaq documents + +=head2 Where to get the perlfaq This document is posted regularly to comp.lang.perl.announce and several other related newsgroups. It is available in a variety of formats from CPAN in the /CPAN/doc/FAQs/FAQ/ directory or on the web at http://www.perl.com/perl/faq/ . -=head2 How to contribute to this document +=head2 How to contribute to the perlfaq You may mail corrections, additions, and suggestions to perlfaq-suggestions@perl.com . This alias should not be