Provided by: libio-all-perl_0.87-1_all bug

NAME

       IO::All - IO::All to Larry Wall!

VERSION

       This document describes IO::All version 0.87.

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
           io('dir/') < io('file.txt');                $ Copy a file to a directory
           io('file.txt') > io('dir/');                # Invokes File::Copy
           io('more.txt') >> io('dir/');               # Add on to a file in the dir

           # 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

       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", "copy", "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.

   In-place Editing
       Because an IO::All object can be used as an array reference, operations on arrays are
       supported transparently (using Tie::File) so a file can be modified in the same way you
       would modify an array.

           > cat > x.txt
           The sexy saxophone,

           got the axe.
           ^d

           > perl -MIO::All -e 'map { s/x/X/g; $_ } @{ io(shift) }' x.txt
           > cat x.txt
           The seXy saXophone,

           got the aXe.

        This one liner uses shift() to grab the file from STDIN and create an io
        object that is dereferenced using @{ } and fed to map() like any perl array
        reference.

   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. eg '| 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 three 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 IO, but they specify options about how the IO
       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
           Adds ":raw" to the list of PerlIO layers applied after "open", and applies it
           immediately on an open handle.

       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.

           Note that "chomp" may cause the following idiom to halt prematurely (e.g., if
           "separator" is "\n" (the default) and "chomp" is in effect, then this command will
           stop reading at the first blank line):

               while ( my $line = $io->getline ) {...}

           Try the following instead:

               while ( defined(my $line = $io->getline) ) {...}

       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. If passed an
           argument, path will be made relative to passed argument.

       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
           Adds ":encoding(UTF-8)" to the list of PerlIO layers applied after "open", and applies
           it immediately on an open handle.

   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
           Adds the specified layer to the list of PerlIO layers applied after "open", and
           applies it immediately on an open handle. Does a bare "binmode" when called without
           argument.

       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
           Adds the specified encoding to the list of PerlIO layers applied after "open", and
           applies it immediately on an open handle. Requires an argument.

       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.

       copy
           Copies the object to the path passed. Works on both files and directories, but
           directories require "File::Copy::Recursive" to be installed.

       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

       Reblessing
           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'.

       Auto-Open
           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.

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

       Auto-Close
           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);

       Explicit open and close
           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.

       Overload
           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.

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.

SEE ALSO

       ·   File::Spec

       ·   File::Path

       ·   File::ReadBackwards

       ·   File::MimeInfo

       ·   IO::Handle

       ·   IO::File

       ·   IO::Dir

       ·   IO::Socket

       ·   Tie::File

AUTHOR

       Ingy döt Net <ingy@cpan.org>

COPYRIGHT AND LICENSE

       Copyright 2004-2017. 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>