1IO::All(3) User Contributed Perl Documentation IO::All(3)
2
6 IO::All - IO::All of it to Graham and Damian!
7
9 use IO::All; # Let the madness begin...
10 # Some of the many ways to read a whole file into a scalar
12 io('file.txt') > $contents; # Overloaded "arrow"
13 $contents < io 'file.txt'; # Flipped but same operation
14 $io = io 'file.txt'; # Create a new IO::All object
15 $contents = $$io; # Overloaded scalar dereference
16 $contents = $io->all; # A method to read everything
17 $contents = $io->slurp; # Another method for that
18 $contents = join '', $io->getlines; # Join the separate lines
19 $contents = join '', map "$_\n", @$io; # Same. Overloaded array deref
20 $io->tie; # Tie the object as a handle
21 $contents = join '', <$io>; # And use it in builtins
22 # and the list goes on ...
23 # Other file operations:
25 @lines = io('file.txt')->slurp; # List context slurp
26 $content > io('file.txt'); # Print to a file
27 io('file.txt')->print($content, $more); # (ditto)
28 $content >> io('file.txt'); # Append to a file
29 io('file.txt')->append($content); # (ditto)
30 $content << $io; # Append to a string
31 io('copy.txt') < io('file.txt'); $ Copy a file
32 io('file.txt') > io('copy.txt'); # Invokes File::Copy
33 io('more.txt') >> io('all.txt'); # Add on to a file
34 # UTF-8 Support
36 $contents = io('file.txt')->utf8->all; # Turn on utf8
37 use IO::All -utf8; # Turn on utf8 for all io
38 $contents = io('file.txt')->all; # by default in this package.
39 # General Encoding Support
41 $contents = io('file.txt')->encoding('big5')->all;
42 use IO::All -encoding => 'big5'; # Turn on big5 for all io
43 $contents = io('file.txt')->all; # by default in this package.
44 # Print the path name of a file:
46 print $io->name; # The direct method
47 print "$io"; # Object stringifies to name
48 print $io; # Quotes not needed here
49 print $io->filename; # The file portion only
50 # Read all the files/directories in a directory:
52 $io = io('my/directory/'); # Create new directory object
53 @contents = $io->all; # Get all contents of dir
54 @contents = @$io; # Directory as an array
55 @contents = values %$io; # Directory as a hash
56 push @contents, $subdir # One at a time
57 while $subdir = $io->next;
58 # Print the name and file type for all the contents above:
60 print "$_ is a " . $_->type . "\n" # Each element of @contents
61 for @contents; # is an IO::All object!!
62 # Print first line of each file:
64 print $_->getline # getline gets one line
65 for io('dir')->all_files; # Files only
66 # Print names of all files/dirs three directories deep:
68 print "$_\n" for $io->all(3); # Pass in the depth. Default=1
69 # Print names of all files/dirs recursively:
71 print "$_\n" for $io->all(0); # Zero means all the way down
72 print "$_\n" for $io->All; # Capitalized shortcut
73 print "$_\n" for $io->deep->all; # Another way
74 # There are some special file names:
76 print io('-'); # Print STDIN to STDOUT
77 io('-') > io('-'); # Do it again
78 io('-') < io('-'); # Same. Context sensitive.
79 "Bad puppy" > io('='); # Message to STDERR
80 $string_file = io('$'); # Create IO::String Object
81 $temp_file = io('?'); # Create a temporary file
82 # Socket operations:
84 $server = io('localhost:5555')->fork; # Create a daemon socket
85 $connection = $server->accept; # Get a connection socket
86 $input < $connection; # Get some data from it
87 "Thank you!" > $connection; # Thank the caller
88 $connection->close; # Hang up
89 io(':6666')->accept->slurp > io->devnull; # Take a complaint and file it
90 # DBM database operations:
92 $dbm = io 'my/database'; # Create a database object
93 print $dbm->{grocery_list}; # Hash context makes it a DBM
94 $dbm->{todo} = $new_list; # Write to database
95 $dbm->dbm('GDBM_file'); # Demand specific DBM
96 io('mydb')->mldbm->{env} = \%ENV; # MLDBM support
97 # Tie::File support:
99 $io = io 'file.txt';
100 $io->[42] = 'Line Forty Three'; # Change a line
101 print $io->[@$io / 2]; # Print middle line
102 @$io = reverse @$io; # Reverse lines in a file
103 # Stat functions:
105 printf "%s %s %s\n", # Print name, uid and size of
106 $_->name, $_->uid, $_->size # contents of current directory
107 for io('.')->all;
108 print "$_\n" for sort # Use mtime method to sort all
109 {$b->mtime <=> $a->mtime} # files under current directory
110 io('.')->All_Files; # by recent modification time.
111 # File::Spec support:
113 $contents < io->catfile(qw(dir file.txt)); # Portable IO operation
114 # Miscellaneous:
116 @lines = io('file.txt')->chomp->slurp; # Chomp as you slurp
117 @chunks =
118 io('file.txt')->separator('xxx')->slurp; # Use alternnate record sep
119 $binary = io('file.bin')->binary->all; # Read a binary file
120 io('a-symlink')->readlink->slurp; # Readlink returns an object
121 print io('foo')->absolute->pathname; # Print absolute path of foo
122 # IO::All External Plugin Methods
124 io("myfile") > io->("ftp://store.org"); # Upload a file using ftp
125 $html < io->http("www.google.com"); # Grab a web page
126 io('mailto:worst@enemy.net')->print($spam); # Email a "friend"
127 # This is just the beginning, read on...
129
131 "Graham Barr for doing it all. Damian Conway for doing it all
132 different."
133 IO::All combines all of the best Perl IO modules into a single nifty
135 object oriented interface to greatly simplify your everyday Perl IO
136 idioms. It exports a single function called "io", which returns a new
137 IO::All object. And that object can do it all!
138 The IO::All object is a proxy for IO::File, IO::Dir, IO::Socket,
140 IO::String, Tie::File, File::Spec, File::Path and File::ReadBackwards;
141 as well as all the DBM and MLDBM modules. You can use most of the
142 methods found in these classes and in IO::Handle (which they inherit
143 from). IO::All adds dozens of other helpful idiomatic methods including
144 file stat and manipulation functions.
145 IO::All is pluggable, and modules like IO::All::LWP and IO::All::Mailto
147 add even more functionality. Optionally, every IO::All object can be
148 tied to itself. This means that you can use most perl IO builtins on
149 it: readline, <>, getc, print, printf, syswrite, sysread, close.
150 The distinguishing magic of IO::All is that it will automatically open
152 (and close) files, directories, sockets and other IO things for you.
153 You never need to specify the mode ('<', '>>', etc), since it is
154 determined by the usage context. That means you can replace this:
155 open STUFF, '<', './mystuff'
157 or die "Can't open './mystuff' for input:\n$!";
158 local $/;
159 my $stuff = <STUFF>;
160 close STUFF;
161 with this:
163 my $stuff < io"./mystuff";
165 And that is a good thing!
167
169 Normally just say:
170 use IO::All;
172 and IO::All will export a single function called "io", which contructs
174 all IO objects.
175 You can also pass global flags like this:
177 use IO::All -strict -encoding => 'big5', -foobar;
179 Which automatically makes those method calls on every new IO object. In
181 other words this:
182 my $io = io('lalala.txt');
184 becomes this:
186 my $io = io('lalala.txt')->strict->encoding('big5')->foobar;
188
190 Here is an alphabetical list of all the public methods that you can
191 call on an IO::All object.
192 "abs2rel", "absolute", "accept", "All", "all", "All_Dirs", "all_dirs",
194 "All_Files", "all_files", "All_Links", "all_links", "append",
195 "appendf", "appendln", "assert", "atime", "autoclose", "autoflush",
196 "backwards", "bcc", "binary", "binmode", "blksize", "blocks",
197 "block_size", "buffer", "canonpath", "case_tolerant", "catdir",
198 "catfile", "catpath", "cc", "chdir", "chomp", "clear", "close",
199 "confess", "content", "ctime", "curdir", "dbm", "deep", "device",
200 "device_id", "devnull", "dir", "domain", "empty", "encoding", "eof",
201 "errors", "file", "filename", "fileno", "filepath", "filter", "fork",
202 "from", "ftp", "get", "getc", "getline", "getlines", "gid", "handle",
203 "head", "http", "https", "inode", "io_handle", "is_absolute", "is_dir",
204 "is_dbm", "is_executable", "is_file", "is_link", "is_mldbm", "is_open",
205 "is_pipe", "is_readable", "is_socket", "is_stdio", "is_string",
206 "is_temp", "is_writable", "join", "length", "link", "lock", "mailer",
207 "mailto", "mkdir", "mkpath", "mldbm", "mode", "modes", "mtime", "name",
208 "new", "next", "nlink", "open", "password", "path", "pathname",
209 "perms", "pipe", "port", "print", "printf", "println", "put", "rdonly",
210 "rdwr", "read", "readdir", "readlink", "recv", "rel2abs", "relative",
211 "rename", "request", "response", "rmdir", "rmtree", "rootdir",
212 "scalar", "seek", "send", "separator", "shutdown", "size", "slurp",
213 "socket", "sort", "splitdir", "splitpath", "stat", "stdio", "stderr",
214 "stdin", "stdout", "strict", "string", "string_ref", "subject",
215 "sysread", "syswrite", "tail", "tell", "temp", "tie", "tmpdir", "to",
216 "touch", "truncate", "type", "user", "uid", "unlink", "unlock",
217 "updir", "uri", "utf8", "utime" and "write".
218 Each method is documented further below.
220
222 IO::All objects overload a small set of Perl operators to great effect.
223 The overloads are limited to <, <<, >, >>, dereferencing operations,
224 and stringification.
225 Even though relatively few operations are overloaded, there is actually
227 a huge matrix of possibilities for magic. That's because the
228 overloading is sensitive to the types, position and context of the
229 arguments, and an IO::All object can be one of many types.
230 The most important overload to grok is stringification. IO::All objects
232 stringify to their file or directory name. Here we print the contents
233 of the current directory:
234 perl -MIO::All -le 'print for io(".")->all'
236 is the same as:
238 perl -MIO::All -le 'print $_->name for io(".")->all'
240 Stringification is important because it allows IO::All operations to
242 return objects when they might otherwise return file names. Then the
243 recipient can use the result either as an object or a string.
244 '>' and '<' move data between objects in the direction pointed to by
246 the operator.
247 $content1 < io('file1');
249 $content1 > io('file2');
250 io('file2') > $content3;
251 io('file3') < $content3;
252 io('file3') > io('file4');
253 io('file5') < io('file4');
254 '>>' and '<<' do the same thing except the recipent string or file is
256 appended to.
257 An IO::All file used as an array reference becomes tied using
259 Tie::File:
260 $file = io"file";
262 # Print last line of file
263 print $file->[-1];
264 # Insert new line in middle of file
265 $file->[$#$file / 2] = 'New line';
266 An IO::All file used as a hash reference becomes tied to a DBM class:
268 io('mydbm')->{ingy} = 'YAML';
270 An IO::All directory used as an array reference, will expose each file
272 or subdirectory as an element of the array.
273 print "$_\n" for @{io 'dir'};
275 IO::All directories used as hash references have file names as keys,
277 and IO::All objects as values:
278 print io('dir')->{'foo.txt'}->slurp;
280 Files used as scalar references get slurped:
282 print ${io('dir')->{'foo.txt'}};
284 Not all combinations of operations and object types are supported. Some
286 just haven't been added yet, and some just don't make sense. If you use
287 an invalid combination, an error will be thrown.
288
290 This section describes some various things that you can easily cook up
291 with IO::All.
292 File Locking
294 IO::All makes it very easy to lock files. Just use the "lock" method.
295 Here's a standalone program that demonstrates locking for both write
296 and read:
297 use IO::All;
299 my $io1 = io('myfile')->lock;
300 $io1->println('line 1');
301 fork or do {
303 my $io2 = io('myfile')->lock;
304 print $io2->slurp;
305 exit;
306 };
307 sleep 1;
309 $io1->println('line 2');
310 $io1->println('line 3');
311 $io1->unlock;
312 There are a lot of subtle things going on here. An exclusive lock is
314 issued for $io1 on the first "println". That's because the file isn't
315 actually opened until the first IO operation.
316 When the child process tries to read the file using $io2, there is a
318 shared lock put on it. Since $io1 has the exclusive lock, the slurp
319 blocks.
320 The parent process sleeps just to make sure the child process gets a
322 chance. The parent needs to call "unlock" or "close" to release the
323 lock. If all goes well the child will print 3 lines.
324 Round Robin
326 This simple example will read lines from a file forever. When the last
327 line is read, it will reopen the file and read the first one again.
328 my $io = io'file1.txt';
330 $io->autoclose(1);
331 while (my $line = $io->getline || $io->getline) {
332 print $line;
333 }
334 Reading Backwards
336 If you call the "backwards" method on an IO::All object, the "getline"
337 and "getlines" will work in reverse. They will read the lines in the
338 file from the end to the beginning.
339 my @reversed;
341 my $io = io('file1.txt');
342 $io->backwards;
343 while (my $line = $io->getline) {
344 push @reversed, $line;
345 }
346 or more simply:
348 my @reversed = io('file1.txt')->backwards->getlines;
350 The "backwards" method returns the IO::All object so that you can chain
352 the calls.
353 NOTE: This operation requires that you have the File::ReadBackwards
355 module installed.
356 Client/Server Sockets
358 IO::All makes it really easy to write a forking socket server and a
359 client to talk to it.
360 In this example, a server will return 3 lines of text, to every client
362 that calls it. Here is the server code:
363 use IO::All;
365 my $socket = io(':12345')->fork->accept;
367 $socket->print($_) while <DATA>;
368 $socket->close;
369 __DATA__
371 On your mark,
372 Get set,
373 Go!
374 Here is the client code:
376 use IO::All;
378 my $io = io('localhost:12345');
380 print while $_ = $io->getline;
381 You can run the server once, and then run the client repeatedly (in
383 another terminal window). It should print the 3 data lines each time.
384 Note that it is important to close the socket if the server is forking,
386 or else the socket won't go out of scope and close.
387 A Tiny Web Server
389 Here is how you could write a simplistic web server that works with
390 static and dynamic pages:
391 perl -MIO::All -e 'io(":8080")->fork->accept->(sub { $_[0] < io(-x $1 ? "./$1 |" : $1) if /^GET \/(.*) / })'
393 There is are a lot of subtle things going on here. First we accept a
395 socket and fork the server. Then we overload the new socket as a code
396 ref. This code ref takes one argument, another code ref, which is used
397 as a callback.
398 The callback is called once for every line read on the socket. The line
400 is put into $_ and the socket itself is passed in to the callback.
401 Our callback is scanning the line in $_ for an HTTP GET request. If one
403 is found it parses the file name into $1. Then we use $1 to create an
404 new IO::All file object... with a twist. If the file is executable
405 ("-x"), then we create a piped command as our IO::All object. This
406 somewhat approximates CGI support.
407 Whatever the resulting object is, we direct the contents back at our
409 socket which is in $_[0]. Pretty simple, eh?
410 DBM Files
412 IO::All file objects used as a hash reference, treat the file as a DBM
413 tied to a hash. Here I write my DB record to STDERR:
414 io("names.db")->{ingy} > io'=';
416 Since their are several DBM formats available in Perl, IO::All picks
418 the first one of these that is installed on your system:
419 DB_File GDBM_File NDBM_File ODBM_File SDBM_File
421 You can override which DBM you want for each IO::All object:
423 my @keys = keys %{io('mydbm')->dbm('SDBM_File')};
425 File Subclassing
427 Subclassing is easy with IO::All. Just create a new module and use
428 IO::All as the base class, like this:
429 package NewModule;
431 use IO::All -base;
432 You need to do it this way so that IO::All will export the "io"
434 function. Here is a simple recipe for subclassing:
435 IO::Dumper inherits everything from IO::All and adds an extra method
437 called "dump", which will dump a data structure to the file we specify
438 in the "io" function. Since it needs Data::Dumper to do the dumping, we
439 override the "open" method to "require Data::Dumper" and then pass
440 control to the real "open".
441 First the code using the module:
443 use IO::Dumper;
445 io('./mydump')->dump($hash);
447 And next the IO::Dumper module itself:
449 package IO::Dumper;
451 use IO::All -base;
452 use Data::Dumper;
453 sub dump {
455 my $self = shift;
456 Dumper(@_) > $self;
457 }
458 1;
460 Inline Subclassing
462 This recipe does the same thing as the previous one, but without
463 needing to write a separate module. The only real difference is the
464 first line. Since you don't "use" IO::Dumper, you need to still call
465 its "import" method manually.
466 IO::Dumper->import;
468 io('./mydump')->dump($hash);
469 package IO::Dumper;
471 use IO::All -base;
472 use Data::Dumper;
473 sub dump {
475 my $self = shift;
476 Dumper(@_) > $self;
477 }
478
480 This section gives a full description of all of the methods that you
481 can call on IO::All objects. The methods have been grouped into
482 subsections based on object construction, option settings,
483 configuration, action methods and support for specific modules.
484 Object Construction and Initialization Methods
486 · new
487 There are three ways to create a new IO::All object. The first is
489 with the special function "io" which really just calls
490 "IO::All->new". The second is by calling "new" as a class method.
491 The third is calling "new" as an object instance method. In this
492 final case, the new objects attributes are copied from the instance
493 object.
494 io(file-descriptor);
496 IO::All->new(file-descriptor);
497 $io->new(file-descriptor);
498 All three forms take a single argument, a file descriptor. A file
500 descriptor can be any of the following:
501 - A file name
503 - A file handle
504 - A directory name
505 - A directory handle
506 - A typeglob reference
507 - A piped shell command. eq '| ls -al'
508 - A socket domain/port. eg 'perl.com:5678'
509 - '-' means STDIN or STDOUT (depending on usage)
510 - '=' means STDERR
511 - '$' means an IO::String object
512 - '?' means a temporary file
513 - A URI including: http, https, ftp and mailto
514 - An IO::All object
515 If you provide an IO::All object, you will simply get that same
517 object returned from the constructor.
518 If no file descriptor is provided, an object will still be created,
520 but it must be defined by one of the following methods before it
521 can be used for I/O:
522 · file
524 io->file(file-name);
526 Using the "file" method sets the type of the object to file and
528 sets the pathname of the file if provided.
529 It might be important to use this method if you had a file whose
531 name was '-', or if the name might otherwise be confused with a
532 directory or a socket. In this case, either of these statements
533 would work the same:
534 my $file = io('-')->file;
536 my $file = io->file('-');
537 · dir
539 io->file(dir-name);
541 Make the object be of type directory.
543 · socket
545 io->file(domain:port);
547 Make the object be of type socket.
549 · link
551 io->file(link-name);
553 Make the object be of type link.
555 · pipe
557 io->file(link-name);
559 Make the object be of type pipe. The following two statements are
561 equivalent:
562 my $io = io('ls -l |');
564 my $io = io('ls -l')->pipe;
565 my $io = io->pipe('ls -l');
566 · dbm
568 This method takes the names of zero or more DBM modules. The first
570 one that is available is used to process the dbm file.
571 io('mydbm')->dbm('NDBM_File', 'SDBM_File')->{author} = 'ingy';
573 If no module names are provided, the first available of the
575 following is used:
576 DB_File GDBM_File NDBM_File ODBM_File SDBM_File
578 · mldbm
580 Similar to the "dbm" method, except create a Multi Level DBM object
582 using the MLDBM module.
583 This method takes the names of zero or more DBM modules and an
585 optional serialization module. The first DBM module that is
586 available is used to process the MLDBM file. The serialization
587 module can be Data::Dumper, Storable or FreezeThaw.
588 io('mymldbm')->mldbm('GDBM_File', 'Storable')->{author} =
590 {nickname => 'ingy'};
591 · string
593 Make the object be a IO::String object. These are equivalent:
595 my $io = io('$');
597 my $io = io->string;
598 · temp
600 Make the object represent a temporary file. It will automatically
602 be open for both read and write.
603 · stdio
605 Make the object represent either STDIN or STDOUT depending on how
607 it is used subsequently. These are equivalent:
608 my $io = io('-');
610 my $io = io->stdin;
611 · stdin
613 Make the object represent STDIN.
615 · stdout
617 Make the object represent STDOUT.
619 · stderr
621 Make the object represent STDERR.
623 · handle
625 io->handle(io-handle);
627 Forces the object to be created from an pre-existing IO handle. You
629 can chain calls together to indicate the type of handle:
630 my $file_object = io->file->handle($file_handle);
632 my $dir_object = io->dir->handle($dir_handle);
633 · http
635 Make the object represent an http uri. Requires IO-All-LWP.
637 · https
639 Make the object represent an https uri. Requires IO-All-LWP.
641 · ftp
643 Make the object represent a ftp uri. Requires IO-All-LWP.
645 · mailto
647 Make the object represent a mailto uri. Requires IO-All-Mailto.
649 If you need to use the same options to create a lot of objects, and
651 don't want to duplicate the code, just create a dummy object with the
652 options you want, and use that object to spawn other objects.
653 my $lt = io->lock->tie;
655 ...
656 my $io1 = $lt->new('file1');
657 my $io2 = $lt->new('file2');
658 Since the new method copies attributes from the calling object, both
660 $io1 and $io2 will be locked and tied.
661 Option Setting Methods
663 The following methods don't do any actual I/O, but they specify options
664 about how the I/O should be done.
665 Each option can take a single argument of 0 or 1. If no argument is
667 given, the value 1 is assumed. Passing 0 turns the option off.
668 All of these options return the object reference that was used to
670 invoke them. This is so that the option methods can be chained
671 together. For example:
672 my $io = io('path/file')->tie->assert->chomp->lock;
674 · absolute
676 Indicates that the "pathname" for the object should be made
678 absolute.
679 · assert
681 This method ensures that the path for a file or directory actually
683 exists before the file is open. If the path does not exist, it is
684 created.
685 · autoclose
687 By default, IO::All will close an object opened for input when EOF
689 is reached. By closing the handle early, one can immediately do
690 other operations on the object without first having to close it.
691 This option is on by default, so if you don't want this behaviour,
693 say so like this:
694 $io->autoclose(0);
696 The object will then be closed when $io goes out of scope, or you
698 manually call "$io->close".
699 · autoflush
701 Proxy for IO::Handle::autoflush
703 · backwards
705 Sets the object to 'backwards' mode. All subsequent "getline"
707 operations will read backwards from the end of the file.
708 Requires the File::ReadBackwards CPAN module.
710 · binary
712 Indicates the file has binary content and should be opened with
714 "binmode".
715 · chdir
717 chdir() to the pathname of a directory object. When object goes out
719 of scope, chdir back to starting directory.
720 · chomp
722 Indicates that all operations that read lines should chomp the
724 lines. If the "separator" method has been called, chomp will remove
725 that value from the end of each record.
726 · confess
728 Errors should be reported with the very detailed Carp::confess
730 function.
731 · deep
733 Indicates that calls to the "all" family of methods should search
735 directories as deep as possible.
736 · fork
738 Indicates that the process should automatically be forked inside
740 the "accept" socket method.
741 · lock
743 Indicate that operations on an object should be locked using flock.
745 · rdonly
747 This option indicates that certain operations like DBM and
749 Tie::File access should be done in read-only mode.
750 · rdwr
752 This option indicates that DBM and MLDBM files should be opened in
754 read- write mode.
755 · relative
757 Indicates that the "pathname" for the object should be made
759 relative.
760 · sort
762 Indicates whether objects returned from one of the "all" methods
764 will be in sorted order by name. True by default.
765 · strict
767 Check the return codes of every single system call. To turn this on
769 for all calls in your module, use:
770 use IO::All -strict;
772 · tie
774 Indicate that the object should be tied to itself, thus allowing it
776 to be used as a filehandle in any of Perl's builtin IO operations.
777 my $io = io('foo')->tie;
779 @lines = <$io>;
780 · utf8
782 Indicates that IO should be done using utf8 encoding. Calls binmode
784 with ":utf8" layer.
785 Configuration Methods
787 The following methods don't do any actual I/O, but they set specific
788 values to configure the IO::All object.
789 If these methods are passed no argument, they will return their current
791 value. If arguments are passed they will be used to set the current
792 value, and the object reference will be returned for potential method
793 chaining.
794 · bcc
796 Set the Bcc field for a mailto object.
798 · binmode
800 Proxy for binmode. Requires a layer to be passed. Use "binary" for
802 plain binary mode.
803 · block_size
805 The default length to be used for "read" and "sysread" calls.
807 Defaults to 1024.
808 · buffer
810 Returns a reference to the internal buffer, which is a scalar. You
812 can use this method to set the buffer to a scalar of your choice.
813 (You can just pass in the scalar, rather than a reference to it.)
814 This is the buffer that "read" and "write" will use by default.
816 You can easily have IO::All objects use the same buffer:
818 my $input = io('abc');
820 my $output = io('xyz');
821 my $buffer;
822 $output->buffer($input->buffer($buffer));
823 $output->write while $input->read;
824 · cc
826 Set the Cc field for a mailto object.
828 · content
830 Get or set the content for an LWP operation manually.
832 · domain
834 Set the domain name or ip address that a socket should use.
836 · encoding
838 Set the encoding to be used for the PerlIO layer.
840 · errors
842 Use this to set a subroutine reference that gets called when an
844 internal error is thrown.
845 · filter
847 Use this to set a subroutine reference that will be used to grep
849 which objects get returned on a call to one of the "all" methods.
850 For example:
851 my @odd = io->curdir->filter(sub {$_->size % 2})->All_Files;
853 @odd will contain all the files under the current directory whose
855 size is an odd number of bytes.
856 · from
858 Indicate the sender for a mailto object.
860 · mailer
862 Set the mailer program for a mailto transaction. Defaults to
864 'sendmail'.
865 · mode
867 Set the mode for which the file should be opened. Examples:
869 $io->mode('>>')->open;
871 $io->mode(O_RDONLY);
872 · name
874 Set or get the name of the file or directory represented by the
876 IO::All object.
877 · password
879 Set the password for an LWP transaction.
881 · perms
883 Sets the permissions to be used if the file/directory needs to be
885 created.
886 · port
888 Set the port number that a socket should use.
890 · request
892 Manually specify the request object for an LWP transaction.
894 · response
896 Returns the resulting reponse object from an LWP transaction.
898 · separator
900 Sets the record (line) separator to whatever value you pass it.
902 Default is \n. Affects the chomp setting too.
903 · string_ref
905 Proxy for IO::String::string_ref
907 Returns a reference to the internal string that is acting like a
909 file.
910 · subject
912 Set the subject for a mailto transaction.
914 · to
916 Set the recipient address for a mailto request.
918 · uri
920 Direct access to the URI used in LWP transactions.
922 · user
924 Set the user name for an LWP transaction.
926 IO Action Methods
928 These are the methods that actually perform I/O operations on an
929 IO::All object. The stat methods and the File::Spec methods are
930 documented in separate sections below.
931 · accept
933 For sockets. Opens a server socket (LISTEN => 1, REUSE => 1).
935 Returns an IO::All socket object that you are listening on.
936 If the "fork" method was called on the object, the process will
938 automatically be forked for every connection.
939 · all
941 Read all contents into a single string.
943 compare(io('file1')->all, io('file2')->all);
945 · all (For directories)
947 Returns a list of IO::All objects for all files and subdirectories
949 in a directory.
950 '.' and '..' are excluded.
952 Takes an optional argument telling how many directories deep to
954 search. The default is 1. Zero (0) means search as deep as
955 possible.
956 The filter method can be used to limit the results.
958 The items returned are sorted by name unless "->sort(0)" is used.
960 · All
962 Same as all(0).
964 · all_dirs
966 Same as "all", but only return directories.
968 · All_Dirs
970 Same as all_dirs(0).
972 · all_files
974 Same as "all", but only return files.
976 · All_Files
978 Same as all_files(0).
980 · all_links
982 Same as "all", but only return links.
984 · All_Links
986 Same as all_links(0).
988 · append
990 Same as print, but sets the file mode to '>>'.
992 · appendf
994 Same as printf, but sets the file mode to '>>'.
996 · appendln
998 Same as println, but sets the file mode to '>>'.
1000 · clear
1002 Clear the internal buffer. This method is called by "write" after
1004 it writes the buffer. Returns the object reference for chaining.
1005 · close
1007 Close will basically unopen the object, which has different
1009 meanings for different objects. For files and directories it will
1010 close and release the handle. For sockets it calls shutdown. For
1011 tied things it unties them, and it unlocks locked things.
1012 · empty
1014 Returns true if a file exists but has no size, or if a directory
1016 exists but has no contents.
1017 · eof
1019 Proxy for IO::Handle::eof
1021 · exists
1023 Returns whether or not the file or directory exists.
1025 · filename
1027 Return the name portion of the file path in the object. For
1029 example:
1030 io('my/path/file.txt')->filename;
1032 would return "file.txt".
1034 · fileno
1036 Proxy for IO::Handle::fileno
1038 · filepath
1040 Return the path portion of the file path in the object. For
1042 example:
1043 io('my/path/file.txt')->filename;
1045 would return "my/path".
1047 · get
1049 Perform an LWP GET request manually.
1051 · getc
1053 Proxy for IO::Handle::getc
1055 · getline
1057 Calls IO::File::getline. You can pass in an optional record
1059 separator.
1060 · getlines
1062 Calls IO::File::getlines. You can pass in an optional record
1064 separator.
1065 · head
1067 Return the first 10 lines of a file. Takes an optional argument
1069 which is the number of lines to return. Works as expected in list
1070 and scalar context. Is subject to the current line separator.
1071 · io_handle
1073 Direct access to the actual IO::Handle object being used on an
1075 opened IO::All object.
1076 · is_dir
1078 Returns boolean telling whether or not the IO::All object
1080 represents a directory.
1081 · is_executable
1083 Returns true if file or directory is executable.
1085 · is_dbm
1087 Returns boolean telling whether or not the IO::All object
1089 represents a dbm file.
1090 · is_file
1092 Returns boolean telling whether or not the IO::All object
1094 represents a file.
1095 · is_link
1097 Returns boolean telling whether or not the IO::All object
1099 represents a symlink.
1100 · is_mldbm
1102 Returns boolean telling whether or not the IO::All object
1104 represents a mldbm file.
1105 · is_open
1107 Indicates whether the IO::All is currently open for input/output.
1109 · is_pipe
1111 Returns boolean telling whether or not the IO::All object
1113 represents a pipe operation.
1114 · is_readable
1116 Returns true if file or directory is readable.
1118 · is_socket
1120 Returns boolean telling whether or not the IO::All object
1122 represents a socket.
1123 · is_stdio
1125 Returns boolean telling whether or not the IO::All object
1127 represents a STDIO file handle.
1128 · is_string
1130 Returns boolean telling whether or not the IO::All object
1132 represents an IO::String object.
1133 · is_temp
1135 Returns boolean telling whether or not the IO::All object
1137 represents a temporary file.
1138 · is_writable
1140 Returns true if file or directory is writable. Can also be spelled
1142 as "is_writeable".
1143 · length
1145 Return the length of the internal buffer.
1147 · mkdir
1149 Create the directory represented by the object.
1151 · mkpath
1153 Create the directory represented by the object, when the path
1155 contains more than one directory that doesn't exist. Proxy for
1156 File::Path::mkpath.
1157 · next
1159 For a directory, this will return a new IO::All object for each
1161 file or subdirectory in the directory. Return undef on EOD.
1162 · open
1164 Open the IO::All object. Takes two optional arguments "mode" and
1166 "perms", which can also be set ahead of time using the "mode" and
1167 "perms" methods.
1168 NOTE: Normally you won't need to call open (or mode/perms), since
1170 this happens automatically for most operations.
1171 · pathname
1173 Return the absolute or relative pathname for a file or directory,
1175 depending on whether object is in "absolute" or "relative" mode.
1176 · print
1178 Proxy for IO::Handle::print
1180 · printf
1182 Proxy for IO::Handle::printf
1184 · println
1186 Same as print, but adds newline to each argument unless it already
1188 ends with one.
1189 · put
1191 Perform an LWP PUT request manually.
1193 · read
1195 This method varies depending on its context. Read carefully (no pun
1197 intended).
1198 For a file, this will proxy IO::File::read. This means you must
1200 pass it a buffer, a length to read, and optionally a buffer offset
1201 for where to put the data that is read. The function returns the
1202 length actually read (which is zero at EOF).
1203 If you don't pass any arguments for a file, IO::All will use its
1205 own internal buffer, a default length, and the offset will always
1206 point at the end of the buffer. The buffer can be accessed with the
1207 "buffer" method. The length can be set with the "block_size"
1208 method. The default length is 1024 bytes. The "clear" method can be
1209 called to clear the buffer.
1210 For a directory, this will proxy IO::Dir::read.
1212 · readdir
1214 Similar to the Perl "readdir" builtin. In scalar context, return
1216 the next directory entry (ie file or directory name), or undef on
1217 end of directory. In list context, return all directory entries.
1218 Note that "readdir" does not return the special "." and ".."
1220 entries.
1221 · readline
1223 Same as "getline".
1225 · readlink
1227 Calls Perl's readlink function on the link represented by the
1229 object. Instead of returning the file path, it returns a new
1230 IO::All object using the file path.
1231 · recv
1233 Proxy for IO::Socket::recv
1235 · rename
1237 my $new = $io->rename('new-name');
1239 Calls Perl's rename function and returns an IO::All object for the
1241 renamed file. Returns false if the rename failed.
1242 · rewind
1244 Proxy for IO::Dir::rewind
1246 · rmdir
1248 Delete the directory represented by the IO::All object.
1250 · rmtree
1252 Delete the directory represented by the IO::All object and all the
1254 files and directories beneath it. Proxy for File::Path::rmtree.
1255 · scalar
1257 Deprecated. Same as "all()".
1259 · seek
1261 Proxy for IO::Handle::seek. If you use seek on an unopened file, it
1263 will be opened for both read and write.
1264 · send
1266 Proxy for IO::Socket::send
1268 · shutdown
1270 Proxy for IO::Socket::shutdown
1272 · slurp
1274 Read all file content in one operation. Returns the file content as
1276 a string. In list context returns every line in the file.
1277 · stat
1279 Proxy for IO::Handle::stat
1281 · sysread
1283 Proxy for IO::Handle::sysread
1285 · syswrite
1287 Proxy for IO::Handle::syswrite
1289 · tail
1291 Return the last 10 lines of a file. Takes an optional argument
1293 which is the number of lines to return. Works as expected in list
1294 and scalar context. Is subject to the current line separator.
1295 · tell
1297 Proxy for IO::Handle::tell
1299 · throw
1301 This is an internal method that gets called whenever there is an
1303 error. It could be useful to override it in a subclass, to provide
1304 more control in error handling.
1305 · touch
1307 Update the atime and mtime values for a file or directory. Creates
1309 an empty file if the file does not exist.
1310 · truncate
1312 Proxy for IO::Handle::truncate
1314 · type
1316 Returns a string indicated the type of io object. Possible values
1318 are:
1319 file
1321 dir
1322 link
1323 socket
1324 string
1325 pipe
1326 Returns undef if type is not determinable.
1328 · unlink
1330 Unlink (delete) the file represented by the IO::All object.
1332 NOTE: You can unlink a file after it is open, and continue using it
1334 until it is closed.
1335 · unlock
1337 Release a lock from an object that used the "lock" method.
1339 · utime
1341 Proxy for the utime Perl function.
1343 · write
1345 Opposite of "read" for file operations only.
1347 NOTE: When used with the automatic internal buffer, "write" will
1349 clear the buffer after writing it.
1350 Stat Methods
1352 This methods get individual values from a stat call on the file,
1353 directory or handle represented by th IO::All object.
1354 · atime
1356 Last access time in seconds since the epoch
1358 · blksize
1360 Preferred block size for file system I/O
1362 · blocks
1364 Actual number of blocks allocated
1366 · ctime
1368 Inode change time in seconds since the epoch
1370 · device
1372 Device number of filesystem
1374 · device_id
1376 Device identifier for special files only
1378 · gid
1380 Numeric group id of file's owner
1382 · inode
1384 Inode number
1386 · modes
1388 File mode - type and permissions
1390 · mtime
1392 Last modify time in seconds since the epoch
1394 · nlink
1396 Number of hard links to the file
1398 · size
1400 Total size of file in bytes
1402 · uid
1404 Numeric user id of file's owner
1406 File::Spec Methods
1408 These methods are all adaptations from File::Spec. Each method actually
1409 does call the matching File::Spec method, but the arguments and return
1410 values differ slightly. Instead of being file and directory names, they
1411 are IO::All objects. Since IO::All objects stringify to their names,
1412 you can generally use the methods just like File::Spec.
1413 · abs2rel
1415 Returns the relative path for the absolute path in the IO::All
1417 object. Can take an optional argument indicating the base path.
1418 · canonpath
1420 Returns the canonical path for the IO::All object.
1422 · case_tolerant
1424 Returns 0 or 1 indicating whether the file system is case tolerant.
1426 Since an active IO::All object is not needed for this function, you
1427 can code it like:
1428 IO::All->case_tolerant;
1430 or more simply:
1432 io->case_tolerant;
1434 · catdir
1436 Concatenate the directory components together, and return a new
1438 IO::All object representing the resulting directory.
1439 · catfile
1441 Concatenate the directory and file components together, and return
1443 a new IO::All object representing the resulting file.
1444 my $contents = io->catfile(qw(dir subdir file))->slurp;
1446 This is a very portable way to read "dir/subdir/file".
1448 · catpath
1450 Concatenate the volume, directory and file components together, and
1452 return a new IO::All object representing the resulting file.
1453 · curdir
1455 Returns an IO::All object representing the current directory.
1457 · devnull
1459 Returns an IO::All object representing the /dev/null file.
1461 · is_absolute
1463 Returns 0 or 1 indicating whether the "name" field of the IO::All
1465 object is an absolute path.
1466 · join
1468 Same as "catfile".
1470 · path
1472 Returns a list of IO::All directory objects for each directory in
1474 your path.
1475 · rel2abs
1477 Returns the absolute path for the relative path in the IO::All
1479 object. Can take an optional argument indicating the base path.
1480 · rootdir
1482 Returns an IO::All object representing the root directory on your
1484 file system.
1485 · splitdir
1487 Returns a list of the directory components of a path in an IO::All
1489 object.
1490 · splitpath
1492 Returns a volume directory and file component of a path in an
1494 IO::All object.
1495 · tmpdir
1497 Returns an IO::All object representing a temporary directory on
1499 your file system.
1500 · updir
1502 Returns an IO::All object representing the current parent
1504 directory.
1505
1507 · Each IO::All object gets reblessed into an IO::All::* object as
1508 soon as IO::All can determine what type of object it should be.
1509 Sometimes it gets reblessed more than once:
1510 my $io = io('mydbm.db');
1512 $io->dbm('DB_File');
1513 $io->{foo} = 'bar';
1514 In the first statement, $io has a reference value of
1516 'IO::All::File', if "mydbm.db" exists. In the second statement, the
1517 object is reblessed into class 'IO::All::DBM'.
1518 · An IO::All object will automatically be opened as soon as there is
1520 enough contextual information to know what type of object it is,
1521 and what mode it should be opened for. This is usually when the
1522 first read or write operation is invoked but might be sooner.
1523 · The mode for an object to be opened with is determined
1525 heuristically unless specified explicitly.
1526 · For input, IO::All objects will automatically be closed after EOF
1528 (or EOD). For output, the object closes when it goes out of scope.
1529 To keep input objects from closing at EOF, do this:
1531 $io->autoclose(0);
1533 · You can always call "open" and "close" explicitly, if you need that
1535 level of control. To test if an object is currently open, use the
1536 "is_open" method.
1537 · Overloaded operations return the target object, if one exists.
1539 This would set $xxx to the IO::All object:
1541 my $xxx = $contents > io('file.txt');
1543 While this would set $xxx to the content string:
1545 my $xxx = $contents < io('file.txt');
1547
1549 The goal of the IO::All project is to continually refine the module to
1550 be as simple and consistent to use as possible. Therefore, in the early
1551 stages of the project, I will not hesitate to break backwards
1552 compatibility with other versions of IO::All if I can find an easier
1553 and clearer way to do a particular thing.
1554 IO is tricky stuff. There is definitely more work to be done. On the
1556 other hand, this module relies heavily on very stable existing IO
1557 modules; so it may work fairly well.
1558 I am sure you will find many unexpected "features". Please send all
1560 problems, ideas and suggestions to ingy@cpan.org.
1561 Known Bugs and Deficiencies
1563 Not all possible combinations of objects and methods have been tested.
1564 There are many many combinations. All of the examples have been tested.
1565 If you find a bug with a particular combination of calls, let me know.
1566 If you call a method that does not make sense for a particular object,
1568 the result probably won't make sense. Little attempt is made to check
1569 for improper usage.
1570
1572 IO::Handle, IO::File, IO::Dir, IO::Socket, IO::String, File::Spec,
1573 File::Path, File::ReadBackwards, Tie::File
1574
1576 A lot of people have sent in suggestions, that have become a part of
1577 IO::All. Thank you.
1578 Special thanks to Ian Langworth for continued testing and patching.
1580 Thank you Simon Cozens for tipping me off to the overloading
1582 possibilities.
1583 Finally, thanks to Autrijus Tang, for always having one more good idea.
1585 (It seems IO::All of it to a lot of people!)
1587
1589 Ingy doet Net <ingy@cpan.org>
1590
1592 Copyright (c) 2004. Brian Ingerson.
1593 Copyright (c) 2006, 2008. Ingy doet Net.
1595 This program is free software; you can redistribute it and/or modify it
1597 under the same terms as Perl itself.
1598 See <http://www.perl.com/perl/misc/Artistic.html>
1600perl v5.12.0 2008-12-12 IO::All(3)