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NAME
    IO::All - IO::All of it to Graham and Damian!

SYNOPSIS
    First, some safe examples:

        use IO::All;

        # Some of the many ways to read a whole file into a scalar
        $contents = io->file('file.txt')->slurp;    # Read an entire file
        @files    = io->dir('lib')->all;            # Get a list of files
        $tail     = io->pipe('-| tail app.log');    # Open a pipe to a command
        $line     = $tail->getline;                 # Read from the pipe

    That said, there are a lot more things that are very convenient and will
    help you write code very quickly, though they should be used
    judiciously:

        use IO::All;                                # Let the madness begin...

        # Some of the many ways to read a whole file into a scalar
        io('file.txt') > $contents;                 # Overloaded "arrow"
        $contents < io 'file.txt';                  # Flipped but same operation
        $io = io 'file.txt';                        # Create a new IO::All object
        $contents = $$io;                           # Overloaded scalar dereference
        $contents = $io->all;                       # A method to read everything
        $contents = $io->slurp;                     # Another method for that
        $contents = join '', $io->getlines;         # Join the separate lines
        $contents = join '', map "$_\n", @$io;      # Same. Overloaded array deref
        $io->tie;                                   # Tie the object as a handle
        $contents = join '', <$io>;                 # And use it in builtins
        # and the list goes on ...

        # Other file operations:
        @lines = io('file.txt')->slurp;             # List context slurp
        $content > io('file.txt');                  # Print to a file
        io('file.txt')->print($content, $more);     # (ditto)
        $content >> io('file.txt');                 # Append to a file
        io('file.txt')->append($content);           # (ditto)
        $content << $io;                            # Append to a string
        io('copy.txt') < io('file.txt');            $ Copy a file
        io('file.txt') > io('copy.txt');            # Invokes File::Copy
        io('more.txt') >> io('all.txt');            # Add on to a file

        # UTF-8 Support
        $contents = io('file.txt')->utf8->all;      # Turn on utf8
        use IO::All -utf8;                          # Turn on utf8 for all io
        $contents = io('file.txt')->all;            #   by default in this package.

        # General Encoding Support
        $contents = io('file.txt')->encoding('big5')->all;
        use IO::All -encoding => 'big5';            # Turn on big5 for all io
        $contents = io('file.txt')->all;            #   by default in this package.

        # Print the path name of a file:
        print $io->name;                            # The direct method
        print "$io";                                # Object stringifies to name
        print $io;                                  # Quotes not needed here
        print $io->filename;                        # The file portion only
        $io->os('win32');                           # change the object to be a
                                                    # win32 path
        print $io->ext;                             # The file extension only
        print $io->mimetype;                        # The mimetype, requires a
                                                    #  working File::MimeType


        # Read all the files/directories in a directory:
        $io = io('my/directory/');                  # Create new directory object
        @contents = $io->all;                       # Get all contents of dir
        @contents = @$io;                           # Directory as an array
        @contents = values %$io;                    # Directory as a hash
        push @contents, $subdir                     # One at a time
          while $subdir = $io->next;

        # Print the name and file type for all the contents above:
        print "$_ is a " . $_->type . "\n"          # Each element of @contents
          for @contents;                            # is an IO::All object!!

        # Print first line of each file:
        print $_->getline                           # getline gets one line
          for io('dir')->all_files;                 # Files only

        # Print names of all files/dirs three directories deep:
        print "$_\n" for $io->all(3);               # Pass in the depth. Default=1

        # Print names of all files/dirs recursively:
        print "$_\n" for $io->all(0);               # Zero means all the way down
        print "$_\n" for $io->All;                  # Capitalized shortcut
        print "$_\n" for $io->deep->all;            # Another way

        # There are some special file names:
        print io('-');                              # Print STDIN to STDOUT
        io('-') > io('-');                          # Do it again
        io('-') < io('-');                          # Same. Context sensitive.
        "Bad puppy" > io('=');                      # Message to STDERR
        $string_file = io('$');                     # Create string based filehandle
        $temp_file = io('?');                       # Create a temporary file

        # Socket operations:
        $server = io('localhost:5555')->fork;       # Create a daemon socket
        $connection = $server->accept;              # Get a connection socket
        $input < $connection;                       # Get some data from it
        "Thank you!" > $connection;                 # Thank the caller
        $connection->close;                         # Hang up
        io(':6666')->accept->slurp > io->devnull;   # Take a complaint and file it

        # DBM database operations:
        $dbm = io 'my/database';                    # Create a database object
        print $dbm->{grocery_list};                 # Hash context makes it a DBM
        $dbm->{todo} = $new_list;                   # Write to database
        $dbm->dbm('GDBM_file');                     # Demand specific DBM
        io('mydb')->mldbm->{env} = \%ENV;           # MLDBM support

        # Tie::File support:
        $io = io 'file.txt';
        $io->[42] = 'Line Forty Three';             # Change a line
        print $io->[@$io / 2];                      # Print middle line
        @$io = reverse @$io;                        # Reverse lines in a file

        # Stat functions:
        printf "%s %s %s\n",                        # Print name, uid and size of
          $_->name, $_->uid, $_->size               # contents of current directory
            for io('.')->all;
        print "$_\n" for sort                       # Use mtime method to sort all
          {$b->mtime <=> $a->mtime}                 # files under current directory
            io('.')->All_Files;                     # by recent modification time.

        # File::Spec support:
        $contents < io->catfile(qw(dir file.txt));  # Portable IO operation

        # Miscellaneous:
        @lines = io('file.txt')->chomp->slurp;      # Chomp as you slurp
        @chunks =
          io('file.txt')->separator('xxx')->slurp;  # Use alternnate record sep
        $binary = io('file.bin')->binary->all;      # Read a binary file
        io('a-symlink')->readlink->slurp;           # Readlink returns an object
        print io('foo')->absolute->pathname;        # Print absolute path of foo

        # IO::All External Plugin Methods
        io("myfile") > io->("ftp://store.org");     # Upload a file using ftp
        $html < io->http("www.google.com");         # Grab a web page
        io('mailto:worst@enemy.net')->print($spam); # Email a "friend"

        # This is just the beginning, read on...

DESCRIPTION
    "Graham Barr for doing it all. Damian Conway for doing it all
    different."

    IO::All combines all of the best Perl IO modules into a single nifty
    object oriented interface to greatly simplify your everyday Perl IO
    idioms. It exports a single function called "io", which returns a new
    IO::All object. And that object can do it all!

    The IO::All object is a proxy for IO::File, IO::Dir, IO::Socket,
    Tie::File, File::Spec, File::Path, File::MimeInfo and
    File::ReadBackwards; as well as all the DBM and MLDBM modules. You can
    use most of the methods found in these classes and in IO::Handle (which
    they inherit from). IO::All adds dozens of other helpful idiomatic
    methods including file stat and manipulation functions.

    IO::All is pluggable, and modules like IO::All::LWP and IO::All::Mailto
    add even more functionality. Optionally, every IO::All object can be
    tied to itself. This means that you can use most perl IO builtins on it:
    readline, <>, getc, print, printf, syswrite, sysread, close.

    The distinguishing magic of IO::All is that it will automatically open
    (and close) files, directories, sockets and other IO things for you. You
    never need to specify the mode ('<', '>>', etc), since it is determined
    by the usage context. That means you can replace this:

        open STUFF, '<', './mystuff'
          or die "Can't open './mystuff' for input:\n$!";
        local $/;
        my $stuff = <STUFF>;
        close STUFF;

    with this:

        my $stuff < io './mystuff';

    And that is a good thing!

USAGE
    Normally just say:

        use IO::All;

    and IO::All will export a single function called "io", which constructs
    all IO objects.

  Note on "io"
    The "io" function is a *magic constructor*. It is easy to use and will
    usually do the right thing, but can also blow up easily.

    It takes a single optional argument and determines what type of IO::All
    subclass object to return. With no arguments it returns an "IO::All"
    object, which has no I/O methods, but has methods to construct subclass
    objects like "IO::All::File".

    In other words, these 2 statements are usually the same:

        $content = io('file.txt')->all;
        $content = io->file('file.txt')->all;

    Use the first form when you are demonstrating your Perl virtues of
    laziness and impatience, and use the second form when your job is on the
    line.

METHOD ROLE CALL
    Here is an alphabetical list of all the public methods that you can call
    on an IO::All object.

    "abs2rel", "absolute", "accept", "All", "all", "All_Dirs", "all_dirs",
    "All_Files", "all_files", "All_Links", "all_links", "append", "appendf",
    "appendln", "assert", "atime", "autoclose", "autoflush", "backwards",
    "bcc", "binary", "binmode", "blksize", "blocks", "block_size", "buffer",
    "canonpath", "case_tolerant", "catdir", "catfile", "catpath", "cc",
    "chdir", "chomp", "clear", "close", "confess", "content", "ctime",
    "curdir", "dbm", "deep", "device", "device_id", "devnull", "dir",
    "domain", "empty", "ext", "encoding", "eof", "errors", "file",
    "filename", "fileno", "filepath", "filter", "fork", "from", "ftp",
    "get", "getc", "getline", "getlines", "gid", "glob", "handle", "head",
    "http", "https", "inode", "io_handle", "is_absolute", "is_dir",
    "is_dbm", "is_executable", "is_file", "is_link", "is_mldbm", "is_open",
    "is_pipe", "is_readable", "is_socket", "is_stdio", "is_string",
    "is_temp", "is_writable", "join", "length", "link", "lock", "mailer",
    "mailto", "mimetype", "mkdir", "mkpath", "mldbm", "mode", "modes",
    "mtime", "name", "new", "next", "nlink", "open", "os" "password",
    "path", "pathname", "perms", "pipe", "port", "print", "printf",
    "println", "put", "rdonly", "rdwr", "read", "readdir", "readlink",
    "recv", "rel2abs", "relative", "rename", "request", "response", "rmdir",
    "rmtree", "rootdir", "scalar", "seek", "send", "separator", "shutdown",
    "size", "slurp", "socket", "sort", "splitdir", "splitpath", "stat",
    "stdio", "stderr", "stdin", "stdout", "string", "string_ref", "subject",
    "sysread", "syswrite", "tail", "tell", "temp", "tie", "tmpdir", "to",
    "touch", "truncate", "type", "user", "uid", "unlink", "unlock", "updir",
    "uri", "utf8", "utime" and "write".

    Each method is documented further below.

OPERATOR OVERLOADING
    IO::All objects overload a small set of Perl operators to great effect.
    The overloads are limited to <, <<, >, >>, dereferencing operations, and
    stringification.

    Even though relatively few operations are overloaded, there is actually
    a huge matrix of possibilities for magic. That's because the overloading
    is sensitive to the types, position and context of the arguments, and an
    IO::All object can be one of many types.

    The most important overload to become familiar with is stringification.
    IO::All objects stringify to their file or directory name. Here we print
    the contents of the current directory:

        perl -MIO::All -le 'print for io(".")->all'

    is the same as:

        perl -MIO::All -le 'print $_->name for io(".")->all'

    Stringification is important because it allows IO::All operations to
    return objects when they might otherwise return file names. Then the
    recipient can use the result either as an object or a string.

    '>' and '<' move data between objects in the direction pointed to by the
    operator.

        $content1 < io('file1');
        $content1 > io('file2');
        io('file2') > $content3;
        io('file3') < $content3;
        io('file3') > io('file4');
        io('file5') < io('file4');

    '>>' and '<<' do the same thing except the recipient string or file is
    appended to.

    An IO::All file used as an array reference becomes tied using Tie::File:

        $file = io "file";
        # Print last line of file
        print $file->[-1];
        # Insert new line in middle of file
        $file->[$#$file / 2] = 'New line';

    An IO::All file used as a hash reference becomes tied to a DBM class:

        io('mydbm')->{ingy} = 'YAML';

    An IO::All directory used as an array reference, will expose each file
    or subdirectory as an element of the array.

        print "$_\n" for @{io 'dir'};

    IO::All directories used as hash references have file names as keys, and
    IO::All objects as values:

        print io('dir')->{'foo.txt'}->slurp;

    Files used as scalar references get slurped:

        print ${io('dir')->{'foo.txt'}};

    Not all combinations of operations and object types are supported. Some
    just haven't been added yet, and some just don't make sense. If you use
    an invalid combination, an error will be thrown.

COOKBOOK
    This section describes some various things that you can easily cook up
    with IO::All.

  File Locking
    IO::All makes it very easy to lock files. Just use the "lock" method.
    Here's a standalone program that demonstrates locking for both write and
    read:

        use IO::All;
        my $io1 = io('myfile')->lock;
        $io1->println('line 1');

        fork or do {
            my $io2 = io('myfile')->lock;
            print $io2->slurp;
            exit;
        };

        sleep 1;
        $io1->println('line 2');
        $io1->println('line 3');
        $io1->unlock;

    There are a lot of subtle things going on here. An exclusive lock is
    issued for $io1 on the first "println". That's because the file isn't
    actually opened until the first IO operation.

    When the child process tries to read the file using $io2, there is a
    shared lock put on it. Since $io1 has the exclusive lock, the slurp
    blocks.

    The parent process sleeps just to make sure the child process gets a
    chance. The parent needs to call "unlock" or "close" to release the
    lock. If all goes well the child will print 3 lines.

  Round Robin
    This simple example will read lines from a file forever. When the last
    line is read, it will reopen the file and read the first one again.

        my $io = io 'file1.txt';
        $io->autoclose(1);
        while (my $line = $io->getline || $io->getline) {
            print $line;
        }

  Reading Backwards
    If you call the "backwards" method on an IO::All object, the "getline"
    and "getlines" will work in reverse. They will read the lines in the
    file from the end to the beginning.

        my @reversed;
        my $io = io('file1.txt');
        $io->backwards;
        while (my $line = $io->getline) {
            push @reversed, $line;
        }

    or more simply:

        my @reversed = io('file1.txt')->backwards->getlines;

    The "backwards" method returns the IO::All object so that you can chain
    the calls.

    NOTE: This operation requires that you have the File::ReadBackwards
    module installed.

  Client/Server Sockets
    IO::All makes it really easy to write a forking socket server and a
    client to talk to it.

    In this example, a server will return 3 lines of text, to every client
    that calls it. Here is the server code:

        use IO::All;

        my $socket = io(':12345')->fork->accept;
        $socket->print($_) while <DATA>;
        $socket->close;

        __DATA__
        On your mark,
        Get set,
        Go!

    Here is the client code:

        use IO::All;

        my $io = io('localhost:12345');
        print while $_ = $io->getline;

    You can run the server once, and then run the client repeatedly (in
    another terminal window). It should print the 3 data lines each time.

    Note that it is important to close the socket if the server is forking,
    or else the socket won't go out of scope and close.

  A Tiny Web Server
    Here is how you could write a simplistic web server that works with
    static and dynamic pages:

        perl -MIO::All -e 'io(":8080")->fork->accept->(sub { $_[0] < io(-x $1 ? "./$1 |" : $1) if /^GET \/(.*) / })'

    There is are a lot of subtle things going on here. First we accept a
    socket and fork the server. Then we overload the new socket as a code
    ref. This code ref takes one argument, another code ref, which is used
    as a callback.

    The callback is called once for every line read on the socket. The line
    is put into $_ and the socket itself is passed in to the callback.

    Our callback is scanning the line in $_ for an HTTP GET request. If one
    is found it parses the file name into $1. Then we use $1 to create an
    new IO::All file object... with a twist. If the file is executable
    ("-x"), then we create a piped command as our IO::All object. This
    somewhat approximates CGI support.

    Whatever the resulting object is, we direct the contents back at our
    socket which is in $_[0]. Pretty simple, eh?

  DBM Files
    IO::All file objects used as a hash reference, treat the file as a DBM
    tied to a hash. Here I write my DB record to STDERR:

        io("names.db")->{ingy} > io('=');

    Since their are several DBM formats available in Perl, IO::All picks the
    first one of these that is installed on your system:

        DB_File GDBM_File NDBM_File ODBM_File SDBM_File

    You can override which DBM you want for each IO::All object:

        my @keys = keys %{io('mydbm')->dbm('SDBM_File')};

  File Subclassing
    Subclassing is easy with IO::All. Just create a new module and use
    IO::All as the base class, like this:

        package NewModule;
        use IO::All -base;

    You need to do it this way so that IO::All will export the "io"
    function. Here is a simple recipe for subclassing:

    IO::Dumper inherits everything from IO::All and adds an extra method
    called "dump", which will dump a data structure to the file we specify
    in the "io" function. Since it needs Data::Dumper to do the dumping, we
    override the "open" method to "require Data::Dumper" and then pass
    control to the real "open".

    First the code using the module:

        use IO::Dumper;

        io('./mydump')->dump($hash);

    And next the IO::Dumper module itself:

        package IO::Dumper;
        use IO::All -base;
        use Data::Dumper;

        sub dump {
            my $self = shift;
            Dumper(@_) > $self;
        }

        1;

  Inline Subclassing
    This recipe does the same thing as the previous one, but without needing
    to write a separate module. The only real difference is the first line.
    Since you don't "use" IO::Dumper, you need to still call its "import"
    method manually.

        IO::Dumper->import;
        io('./mydump')->dump($hash);

        package IO::Dumper;
        use IO::All -base;
        use Data::Dumper;

        sub dump {
            my $self = shift;
            Dumper(@_) > $self;
        }

THE IO::All METHODS
    This section gives a full description of all of the methods that you can
    call on IO::All objects. The methods have been grouped into subsections
    based on object construction, option settings, configuration, action
    methods and support for specific modules.

  Object Construction and Initialization Methods
    *   new

        There are three ways to create a new IO::All object. The first is
        with the special function "io" which really just calls
        "IO::All->new". The second is by calling "new" as a class method.
        The third is calling "new" as an object instance method. In this
        final case, the new objects attributes are copied from the instance
        object.

            io(file-descriptor);
            IO::All->new(file-descriptor);
            $io->new(file-descriptor);

        All three forms take a single argument, a file descriptor. A file
        descriptor can be any of the following:

            - A file name
            - A file handle
            - A directory name
            - A directory handle
            - A typeglob reference
            - A piped shell command. eq '| ls -al'
            - A socket domain/port.  eg 'perl.com:5678'
            - '-' means STDIN or STDOUT (depending on usage)
            - '=' means STDERR
            - '$' means an in memory filehandle object
            - '?' means a temporary file
            - A URI including: http, https, ftp and mailto
            - An IO::All object

        If you provide an IO::All object, you will simply get that *same
        object* returned from the constructor.

        If no file descriptor is provided, an object will still be created,
        but it must be defined by one of the following methods before it can
        be used for I/O:

    *   file

            io->file("path/to/my/file.txt");

        Using the "file" method sets the type of the object to *file* and
        sets the pathname of the file if provided.

        It might be important to use this method if you had a file whose
        name was '-', or if the name might otherwise be confused with a
        directory or a socket. In this case, either of these statements
        would work the same:

            my $file = io('-')->file;
            my $file = io->file('-');

    *   dir

            io->dir($dir_name);

        Make the object be of type *directory*.

    *   socket

            io->socket("${domain}:${port}");

        Make the object be of type *socket*.

    *   link

            io->link($link_name);

        Make the object be of type *link*.

    *   pipe

            io->pipe($pipe_command);

        Make the object be of type *pipe*. The following two statements are
        equivalent:

            my $io = io('ls -l |');
            my $io = io('ls -l')->pipe;
            my $io = io->pipe('ls -l');

    *   dbm

        This method takes the names of zero or more DBM modules. The first
        one that is available is used to process the dbm file.

            io('mydbm')->dbm('NDBM_File', 'SDBM_File')->{author} = 'ingy';

        If no module names are provided, the first available of the
        following is used:

            DB_File GDBM_File NDBM_File ODBM_File SDBM_File

    *   mldbm

        Similar to the "dbm" method, except create a Multi Level DBM object
        using the MLDBM module.

        This method takes the names of zero or more DBM modules and an
        optional serialization module. The first DBM module that is
        available is used to process the MLDBM file. The serialization
        module can be Data::Dumper, Storable or FreezeThaw.

            io('mymldbm')->mldbm('GDBM_File', 'Storable')->{author} =
              {nickname => 'ingy'};

    *   string

        Make the object be an in memory filehandle. These are equivalent:

            my $io = io('$');
            my $io = io->string;

    *   temp

        Make the object represent a temporary file. It will automatically be
        open for both read and write.

    *   stdio

        Make the object represent either STDIN or STDOUT depending on how it
        is used subsequently. These are equivalent:

            my $io = io('-');
            my $io = io->stdin;

    *   stdin

        Make the object represent STDIN.

    *   stdout

        Make the object represent STDOUT.

    *   stderr

        Make the object represent STDERR.

    *   handle

            io->handle($io_handle);

        Forces the object to be created from an pre-existing IO handle. You
        can chain calls together to indicate the type of handle:

            my $file_object = io->file->handle($file_handle);
            my $dir_object = io->dir->handle($dir_handle);

    *   http

        Make the object represent an HTTP URI. Requires IO-All-LWP.

    *   https

        Make the object represent an HTTPS URI. Requires IO-All-LWP.

    *   ftp

        Make the object represent an FTP URI. Requires IO-All-LWP.

    *   mailto

        Make the object represent a "mailto:" URI. Requires IO-All-Mailto.

    If you need to use the same options to create a lot of objects, and
    don't want to duplicate the code, just create a dummy object with the
    options you want, and use that object to spawn other objects.

        my $lt = io->lock->tie;
        ...
        my $io1 = $lt->new('file1');
        my $io2 = $lt->new('file2');

    Since the new method copies attributes from the calling object, both
    $io1 and $io2 will be locked and tied.

  Option Setting Methods
    The following methods don't do any actual I/O, but they specify options
    about how the I/O should be done.

    Each option can take a single argument of 0 or 1. If no argument is
    given, the value 1 is assumed. Passing 0 turns the option off.

    All of these options return the object reference that was used to invoke
    them. This is so that the option methods can be chained together. For
    example:

        my $io = io('path/file')->tie->assert->chomp->lock;

    *   absolute

        Indicates that the "pathname" for the object should be made
        absolute.

            # Print the full path of the current working directory
            # (like pwd).

            use IO::All;

            print io->curdir->absolute;

    *   assert

        This method ensures that the path for a file or directory actually
        exists before the file is open. If the path does not exist, it is
        created.

        For example, here is a program called "create-cat-to" that outputs
        to a file that it creates.

            #!/usr/bin/perl

            # create-cat-to.pl
            # cat to a file that can be created.

            use strict;
            use warnings;

            use IO::All;

            my $filename = shift(@ARGV);

            # Create a file called $filename, including all leading components.
            io('-') > io->file($filename)->assert;

        Here's an example use of it:

            $ ls -l
            total 0
            $ echo "Hello World" | create-cat-to one/two/three/four.txt
            $ ls -l
            total 4
            drwxr-xr-x 3 shlomif shlomif 4096 2010-10-14 18:03 one/
            $ cat one/two/three/four.txt
            Hello World
            $

    *   autoclose

        By default, IO::All will close an object opened for input when EOF
        is reached. By closing the handle early, one can immediately do
        other operations on the object without first having to close it.

        This option is on by default, so if you don't want this behaviour,
        say so like this:

            $io->autoclose(0);

        The object will then be closed when $io goes out of scope, or you
        manually call "$io->close".

    *   autoflush

        Proxy for IO::Handle::autoflush

    *   backwards

        Sets the object to 'backwards' mode. All subsequent "getline"
        operations will read backwards from the end of the file.

        Requires the File::ReadBackwards CPAN module.

    *   binary

        Indicates the file has binary content and should be opened with
        "binmode".

    *   chdir

        chdir() to the pathname of a directory object. When object goes out
        of scope, chdir back to starting directory.

    *   chomp

        Indicates that all operations that read lines should chomp the
        lines. If the "separator" method has been called, chomp will remove
        that value from the end of each record.

    *   confess

        Errors should be reported with the very detailed Carp::confess
        function.

    *   deep

        Indicates that calls to the "all" family of methods should search
        directories as deep as possible.

    *   fork

        Indicates that the process should automatically be forked inside the
        "accept" socket method.

    *   lock

        Indicate that operations on an object should be locked using flock.

    *   rdonly

        This option indicates that certain operations like DBM and Tie::File
        access should be done in read-only mode.

    *   rdwr

        This option indicates that DBM and MLDBM files should be opened in
        read- write mode.

    *   relative

        Indicates that the "pathname" for the object should be made
        relative.

    *   sort

        Indicates whether objects returned from one of the "all" methods
        will be in sorted order by name. True by default.

    *   tie

        Indicate that the object should be tied to itself, thus allowing it
        to be used as a filehandle in any of Perl's builtin IO operations.

            my $io = io('foo')->tie;
            @lines = <$io>;

    *   utf8

        Indicates that IO should be done using utf8 encoding. Calls binmode
        with ":utf8" layer.

  Configuration Methods
    The following methods don't do any actual I/O, but they set specific
    values to configure the IO::All object.

    If these methods are passed no argument, they will return their current
    value. If arguments are passed they will be used to set the current
    value, and the object reference will be returned for potential method
    chaining.

    *   bcc

        Set the Bcc field for a mailto object.

    *   binmode

        Proxy for binmode. Requires a layer to be passed. Use "binary" for
        plain binary mode.

    *   block_size

        The default length to be used for "read" and "sysread" calls.
        Defaults to 1024.

    *   buffer

        Returns a reference to the internal buffer, which is a scalar. You
        can use this method to set the buffer to a scalar of your choice.
        (You can just pass in the scalar, rather than a reference to it.)

        This is the buffer that "read" and "write" will use by default.

        You can easily have IO::All objects use the same buffer:

            my $input = io('abc');
            my $output = io('xyz');
            my $buffer;
            $output->buffer($input->buffer($buffer));
            $output->write while $input->read;

    *   cc

        Set the Cc field for a mailto object.

    *   content

        Get or set the content for an LWP operation manually.

    *   domain

        Set the domain name or ip address that a socket should use.

    *   encoding

        Set the encoding to be used for the PerlIO layer.

    *   errors

        Use this to set a subroutine reference that gets called when an
        internal error is thrown.

    *   filter

        Use this to set a subroutine reference that will be used to grep
        which objects get returned on a call to one of the "all" methods.
        For example:

            my @odd = io->curdir->filter(sub {$_->size % 2})->All_Files;

        @odd will contain all the files under the current directory whose
        size is an odd number of bytes.

    *   from

        Indicate the sender for a mailto object.

    *   mailer

        Set the mailer program for a mailto transaction. Defaults to
        'sendmail'.

    *   mode

        Set the mode for which the file should be opened. Examples:

            $io->mode('>>')->open;
            $io->mode(O_RDONLY);

            my $log_appender = io->file('/var/log/my-application.log')
                                 ->mode('>>')->open();

            $log_appender->print("Stardate 5987.6: Mission accomplished.");

    *   name

        Set or get the name of the file or directory represented by the
        IO::All object.

    *   password

        Set the password for an LWP transaction.

    *   perms

        Sets the permissions to be used if the file/directory needs to be
        created.

    *   port

        Set the port number that a socket should use.

    *   request

        Manually specify the request object for an LWP transaction.

    *   response

        Returns the resulting response object from an LWP transaction.

    *   separator

        Sets the record (line) separator to whatever value you pass it.
        Default is \n. Affects the chomp setting too.

    *   string_ref

        Returns a reference to the internal string that is acting like a
        file.

    *   subject

        Set the subject for a mailto transaction.

    *   to

        Set the recipient address for a mailto request.

    *   uri

        Direct access to the URI used in LWP transactions.

    *   user

        Set the user name for an LWP transaction.

  IO Action Methods
    These are the methods that actually perform I/O operations on an IO::All
    object. The stat methods and the File::Spec methods are documented in
    separate sections below.

    *   accept

        For sockets. Opens a server socket (LISTEN => 1, REUSE => 1).
        Returns an IO::All socket object that you are listening on.

        If the "fork" method was called on the object, the process will
        automatically be forked for every connection.

    *   all

        Read all contents into a single string.

            compare(io('file1')->all, io('file2')->all);

    *   all (For directories)

        Returns a list of IO::All objects for all files and subdirectories
        in a directory.

        '.' and '..' are excluded.

        Takes an optional argument telling how many directories deep to
        search. The default is 1. Zero (0) means search as deep as possible.

        The filter method can be used to limit the results.

        The items returned are sorted by name unless "->sort(0)" is used.

    *   All

        Same as all(0).

    *   all_dirs

        Same as "all", but only return directories.

    *   All_Dirs

        Same as all_dirs(0).

    *   all_files

        Same as "all", but only return files.

    *   All_Files

        Same as all_files(0).

    *   all_links

        Same as "all", but only return links.

    *   All_Links

        Same as all_links(0).

    *   append

        Same as print, but sets the file mode to '>>'.

    *   appendf

        Same as printf, but sets the file mode to '>>'.

    *   appendln

        Same as println, but sets the file mode to '>>'.

    *   clear

        Clear the internal buffer. This method is called by "write" after it
        writes the buffer. Returns the object reference for chaining.

    *   close

        Close will basically unopen the object, which has different meanings
        for different objects. For files and directories it will close and
        release the handle. For sockets it calls shutdown. For tied things
        it unties them, and it unlocks locked things.

    *   empty

        Returns true if a file exists but has no size, or if a directory
        exists but has no contents.

    *   eof

        Proxy for IO::Handle::eof

    *   ext

        Returns the extension of the file. Can also be spelled as
        "extension"

    *   exists

        Returns whether or not the file or directory exists.

    *   filename

        Return the name portion of the file path in the object. For example:

            io('my/path/file.txt')->filename;

        would return "file.txt".

    *   fileno

        Proxy for IO::Handle::fileno

    *   filepath

        Return the path portion of the file path in the object. For example:

            io('my/path/file.txt')->filepath;

        would return "my/path".

    *   get

        Perform an LWP GET request manually.

    *   getc

        Proxy for IO::Handle::getc

    *   getline

        Calls IO::File::getline. You can pass in an optional record
        separator.

    *   getlines

        Calls IO::File::getlines. You can pass in an optional record
        separator.

    *   glob

        Creates IO::All objects for the files matching the glob in the
        IO::All::Dir. For example:

            io->dir($ENV{HOME})->glob('*.txt')

    *   head

        Return the first 10 lines of a file. Takes an optional argument
        which is the number of lines to return. Works as expected in list
        and scalar context. Is subject to the current line separator.

    *   io_handle

        Direct access to the actual IO::Handle object being used on an
        opened IO::All object.

    *   is_dir

        Returns boolean telling whether or not the IO::All object represents
        a directory.

    *   is_executable

        Returns true if file or directory is executable.

    *   is_dbm

        Returns boolean telling whether or not the IO::All object represents
        a dbm file.

    *   is_file

        Returns boolean telling whether or not the IO::All object represents
        a file.

    *   is_link

        Returns boolean telling whether or not the IO::All object represents
        a symlink.

    *   is_mldbm

        Returns boolean telling whether or not the IO::All object represents
        a mldbm file.

    *   is_open

        Indicates whether the IO::All is currently open for input/output.

    *   is_pipe

        Returns boolean telling whether or not the IO::All object represents
        a pipe operation.

    *   is_readable

        Returns true if file or directory is readable.

    *   is_socket

        Returns boolean telling whether or not the IO::All object represents
        a socket.

    *   is_stdio

        Returns boolean telling whether or not the IO::All object represents
        a STDIO file handle.

    *   is_string

        Returns boolean telling whether or not the IO::All object represents
        an in memory filehandle.

    *   is_temp

        Returns boolean telling whether or not the IO::All object represents
        a temporary file.

    *   is_writable

        Returns true if file or directory is writable. Can also be spelled
        as "is_writeable".

    *   length

        Return the length of the internal buffer.

    *   mimetype

        Return the mimetype of the file.

        Requires a working installation of the File::MimeInfo CPAN module.

    *   mkdir

        Create the directory represented by the object.

    *   mkpath

        Create the directory represented by the object, when the path
        contains more than one directory that doesn't exist. Proxy for
        File::Path::mkpath.

    *   next

        For a directory, this will return a new IO::All object for each file
        or subdirectory in the directory. Return undef on EOD.

    *   open

        Open the IO::All object. Takes two optional arguments "mode" and
        "perms", which can also be set ahead of time using the "mode" and
        "perms" methods.

        NOTE: Normally you won't need to call open (or mode/perms), since
        this happens automatically for most operations.

    *   os

        Change the object's os representation. Valid options are: "win32",
        "unix", "vms", "mac", "os2".

    *   pathname

        Return the absolute or relative pathname for a file or directory,
        depending on whether object is in "absolute" or "relative" mode.

    *   print

        Proxy for IO::Handle::print

    *   printf

        Proxy for IO::Handle::printf

    *   println

        Same as print, but adds newline to each argument unless it already
        ends with one.

    *   put

        Perform an LWP PUT request manually.

    *   read

        This method varies depending on its context. Read carefully (no pun
        intended).

        For a file, this will proxy IO::File::read. This means you must pass
        it a buffer, a length to read, and optionally a buffer offset for
        where to put the data that is read. The function returns the length
        actually read (which is zero at EOF).

        If you don't pass any arguments for a file, IO::All will use its own
        internal buffer, a default length, and the offset will always point
        at the end of the buffer. The buffer can be accessed with the
        "buffer" method. The length can be set with the "block_size" method.
        The default length is 1024 bytes. The "clear" method can be called
        to clear the buffer.

        For a directory, this will proxy IO::Dir::read.

    *   readdir

        Similar to the Perl "readdir" builtin. In scalar context, return the
        next directory entry (ie file or directory name), or undef on end of
        directory. In list context, return all directory entries.

        Note that "readdir" does not return the special "." and ".."
        entries.

    *   readline

        Same as "getline".

    *   readlink

        Calls Perl's readlink function on the link represented by the
        object. Instead of returning the file path, it returns a new IO::All
        object using the file path.

    *   recv

        Proxy for IO::Socket::recv

    *   rename

            my $new = $io->rename('new-name');

        Calls Perl's rename function and returns an IO::All object for the
        renamed file. Returns false if the rename failed.

    *   rewind

        Proxy for IO::Dir::rewind

    *   rmdir

        Delete the directory represented by the IO::All object.

    *   rmtree

        Delete the directory represented by the IO::All object and all the
        files and directories beneath it. Proxy for File::Path::rmtree.

    *   scalar

        Deprecated. Same as "all()".

    *   seek

        Proxy for IO::Handle::seek. If you use seek on an unopened file, it
        will be opened for both read and write.

    *   send

        Proxy for IO::Socket::send

    *   shutdown

        Proxy for IO::Socket::shutdown

    *   slurp

        Read all file content in one operation. Returns the file content as
        a string. In list context returns every line in the file.

    *   stat

        Proxy for IO::Handle::stat

    *   sysread

        Proxy for IO::Handle::sysread

    *   syswrite

        Proxy for IO::Handle::syswrite

    *   tail

        Return the last 10 lines of a file. Takes an optional argument which
        is the number of lines to return. Works as expected in list and
        scalar context. Is subject to the current line separator.

    *   tell

        Proxy for IO::Handle::tell

    *   throw

        This is an internal method that gets called whenever there is an
        error. It could be useful to override it in a subclass, to provide
        more control in error handling.

    *   touch

        Update the atime and mtime values for a file or directory. Creates
        an empty file if the file does not exist.

    *   truncate

        Proxy for IO::Handle::truncate

    *   type

        Returns a string indicated the type of io object. Possible values
        are:

            file
            dir
            link
            socket
            string
            pipe

        Returns undef if type is not determinable.

    *   unlink

        Unlink (delete) the file represented by the IO::All object.

        NOTE: You can unlink a file after it is open, and continue using it
        until it is closed.

    *   unlock

        Release a lock from an object that used the "lock" method.

    *   utime

        Proxy for the utime Perl function.

    *   write

        Opposite of "read" for file operations only.

        NOTE: When used with the automatic internal buffer, "write" will
        clear the buffer after writing it.

  Stat Methods
    This methods get individual values from a stat call on the file,
    directory or handle represented by the IO::All object.

    *   atime

        Last access time in seconds since the epoch

    *   blksize

        Preferred block size for file system I/O

    *   blocks

        Actual number of blocks allocated

    *   ctime

        Inode change time in seconds since the epoch

    *   device

        Device number of filesystem

    *   device_id

        Device identifier for special files only

    *   gid

        Numeric group id of file's owner

    *   inode

        Inode number

    *   modes

        File mode - type and permissions

    *   mtime

        Last modify time in seconds since the epoch

    *   nlink

        Number of hard links to the file

    *   size

        Total size of file in bytes

    *   uid

        Numeric user id of file's owner

  File::Spec Methods
    These methods are all adaptations from File::Spec. Each method actually
    does call the matching File::Spec method, but the arguments and return
    values differ slightly. Instead of being file and directory names, they
    are IO::All objects. Since IO::All objects stringify to their names, you
    can generally use the methods just like File::Spec.

    *   abs2rel

        Returns the relative path for the absolute path in the IO::All
        object. Can take an optional argument indicating the base path.

    *   canonpath

        Returns the canonical path for the IO::All object. The canonical
        path is the fully resolved path if the file exists, so any symlinks
        will be resolved.

    *   case_tolerant

        Returns 0 or 1 indicating whether the file system is case tolerant.
        Since an active IO::All object is not needed for this function, you
        can code it like:

            IO::All->case_tolerant;

        or more simply:

            io->case_tolerant;

    *   catdir

        Concatenate the directory components together, and return a new
        IO::All object representing the resulting directory.

    *   catfile

        Concatenate the directory and file components together, and return a
        new IO::All object representing the resulting file.

            my $contents = io->catfile(qw(dir subdir file))->slurp;

        This is a very portable way to read "dir/subdir/file".

    *   catpath

        Concatenate the volume, directory and file components together, and
        return a new IO::All object representing the resulting file.

    *   curdir

        Returns an IO::All object representing the current directory.

    *   devnull

        Returns an IO::All object representing the /dev/null file.

    *   is_absolute

        Returns 0 or 1 indicating whether the "name" field of the IO::All
        object is an absolute path.

    *   join

        Same as "catfile".

    *   path

        Returns a list of IO::All directory objects for each directory in
        your path.

    *   rel2abs

        Returns the absolute path for the relative path in the IO::All
        object. Can take an optional argument indicating the base path.

    *   rootdir

        Returns an IO::All object representing the root directory on your
        file system.

    *   splitdir

        Returns a list of the directory components of a path in an IO::All
        object.

    *   splitpath

        Returns a volume directory and file component of a path in an
        IO::All object.

    *   tmpdir

        Returns an IO::All object representing a temporary directory on your
        file system.

    *   updir

        Returns an IO::All object representing the current parent directory.

OPERATIONAL NOTES
    *   Each IO::All object gets reblessed into an IO::All::* object as soon
        as IO::All can determine what type of object it should be. Sometimes
        it gets reblessed more than once:

            my $io = io('mydbm.db');
            $io->dbm('DB_File');
            $io->{foo} = 'bar';

        In the first statement, $io has a reference value of
        'IO::All::File', if "mydbm.db" exists. In the second statement, the
        object is reblessed into class 'IO::All::DBM'.

    *   An IO::All object will automatically be opened as soon as there is
        enough contextual information to know what type of object it is, and
        what mode it should be opened for. This is usually when the first
        read or write operation is invoked but might be sooner.

    *   The mode for an object to be opened with is determined heuristically
        unless specified explicitly.

    *   For input, IO::All objects will automatically be closed after EOF
        (or EOD). For output, the object closes when it goes out of scope.

        To keep input objects from closing at EOF, do this:

            $io->autoclose(0);

    *   You can always call "open" and "close" explicitly, if you need that
        level of control. To test if an object is currently open, use the
        "is_open" method.

    *   Overloaded operations return the target object, if one exists.

        This would set $xxx to the IO::All object:

            my $xxx = $contents > io('file.txt');

        While this would set $xxx to the content string:

            my $xxx = $contents < io('file.txt');

STABILITY
    The goal of the IO::All project is to continually refine the module to
    be as simple and consistent to use as possible. Therefore, in the early
    stages of the project, I will not hesitate to break backwards
    compatibility with other versions of IO::All if I can find an easier and
    clearer way to do a particular thing.

    IO is tricky stuff. There is definitely more work to be done. On the
    other hand, this module relies heavily on very stable existing IO
    modules; so it may work fairly well.

    I am sure you will find many unexpected "features". Please send all
    problems, ideas and suggestions to ingy@cpan.org.

  Known Bugs and Deficiencies
    Not all possible combinations of objects and methods have been tested.
    There are many many combinations. All of the examples have been tested.
    If you find a bug with a particular combination of calls, let me know.

    If you call a method that does not make sense for a particular object,
    the result probably won't make sense. Little attempt is made to check
    for improper usage.

SEE ALSO
    IO::Handle, IO::File, IO::Dir, IO::Socket, File::Spec, File::Path,
    File::ReadBackwards, Tie::File, File::MimeInfo

CREDITS
    A lot of people have sent in suggestions, that have become a part of
    IO::All. Thank you.

    Special thanks to Ian Langworth for continued testing and patching.

    Thank you Simon Cozens for tipping me off to the overloading
    possibilities.

    Finally, thanks to Autrijus Tang, for always having one more good idea.

    (It seems IO::All of it to a lot of people!)

REPOSITORY AND COMMUNITY
    The IO::All module can be found on CPAN and on GitHub:
    <http://github.com/ingydotnet/io-all-pm>.

    Please join the IO::All discussion on #io-all on irc.perl.org.

AUTHOR
    Ingy döt Net <ingy@cpan.org>

COPYRIGHT
    Copyright (c) 2004. Brian Ingerson.

    Copyright (c) 2006, 2008, 2010. Ingy döt Net.

    This program is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself.

    See <http://www.perl.com/perl/misc/Artistic.html>