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+package FileHandle;
+
+require 5.003;
+use strict;
+use vars qw($VERSION @ISA @EXPORT @EXPORT_OK);
+
+$VERSION = "2.00";
+
+require IO::File;
+@ISA = qw(IO::File);
+
+@EXPORT = qw(_IOFBF _IOLBF _IONBF);
+
+@EXPORT_OK = qw(
+ pipe
+
+ autoflush
+ output_field_separator
+ output_record_separator
+ input_record_separator
+ input_line_number
+ format_page_number
+ format_lines_per_page
+ format_lines_left
+ format_name
+ format_top_name
+ format_line_break_characters
+ format_formfeed
+
+ print
+ printf
+ getline
+ getlines
+);
+
+#
+# Everything we're willing to export, we must first import.
+#
+import IO::Handle grep { !defined(&$_) } @EXPORT, @EXPORT_OK;
+
+#
+# Specialized importer for Fcntl magic.
+#
+sub import {
+ my $pkg = shift;
+ my $callpkg = caller;
+ Exporter::export $pkg, $callpkg, @_;
+
+ #
+ # If the Fcntl extension is available,
+ # export its constants.
+ #
+ eval {
+ require Fcntl;
+ Exporter::export 'Fcntl', $callpkg;
+ };
+}
+
+################################################
+# This is the only exported function we define;
+# the rest come from other classes.
+#
+
+sub pipe {
+ my $r = new IO::Handle;
+ my $w = new IO::Handle;
+ CORE::pipe($r, $w) or return undef;
+ ($r, $w);
+}
+
+1;
+
+__END__
+
+=head1 NAME
+
+FileHandle - supply object methods for filehandles
+
+=head1 SYNOPSIS
+
+ use FileHandle;
+
+ $fh = new FileHandle;
+ if ($fh->open "< file") {
+ print <$fh>;
+ $fh->close;
+ }
+
+ $fh = new FileHandle "> FOO";
+ if (defined $fh) {
+ print $fh "bar\n";
+ $fh->close;
+ }
+
+ $fh = new FileHandle "file", "r";
+ if (defined $fh) {
+ print <$fh>;
+ undef $fh; # automatically closes the file
+ }
+
+ $fh = new FileHandle "file", O_WRONLY|O_APPEND;
+ if (defined $fh) {
+ print $fh "corge\n";
+ undef $fh; # automatically closes the file
+ }
+
+ $pos = $fh->getpos;
+ $fh->setpos $pos;
+
+ $fh->setvbuf($buffer_var, _IOLBF, 1024);
+
+ ($readfh, $writefh) = FileHandle::pipe;
+
+ autoflush STDOUT 1;
+
+=head1 DESCRIPTION
+
+NOTE: This class is now a front-end to the IO::* classes.
+
+C<FileHandle::new> creates a C<FileHandle>, which is a reference to a
+newly created symbol (see the C<Symbol> package). If it receives any
+parameters, they are passed to C<FileHandle::open>; if the open fails,
+the C<FileHandle> object is destroyed. Otherwise, it is returned to
+the caller.
+
+C<FileHandle::new_from_fd> creates a C<FileHandle> like C<new> does.
+It requires two parameters, which are passed to C<FileHandle::fdopen>;
+if the fdopen fails, the C<FileHandle> object is destroyed.
+Otherwise, it is returned to the caller.
+
+C<FileHandle::open> accepts one parameter or two. With one parameter,
+it is just a front end for the built-in C<open> function. With two
+parameters, the first parameter is a filename that may include
+whitespace or other special characters, and the second parameter is
+the open mode, optionally followed by a file permission value.
+
+If C<FileHandle::open> receives a Perl mode string (">", "+<", etc.)
+or a POSIX fopen() mode string ("w", "r+", etc.), it uses the basic
+Perl C<open> operator.
+
+If C<FileHandle::open> is given a numeric mode, it passes that mode
+and the optional permissions value to the Perl C<sysopen> operator.
+For convenience, C<FileHandle::import> tries to import the O_XXX
+constants from the Fcntl module. If dynamic loading is not available,
+this may fail, but the rest of FileHandle will still work.
+
+C<FileHandle::fdopen> is like C<open> except that its first parameter
+is not a filename but rather a file handle name, a FileHandle object,
+or a file descriptor number.
+
+If the C functions fgetpos() and fsetpos() are available, then
+C<FileHandle::getpos> returns an opaque value that represents the
+current position of the FileHandle, and C<FileHandle::setpos> uses
+that value to return to a previously visited position.
+
+If the C function setvbuf() is available, then C<FileHandle::setvbuf>
+sets the buffering policy for the FileHandle. The calling sequence
+for the Perl function is the same as its C counterpart, including the
+macros C<_IOFBF>, C<_IOLBF>, and C<_IONBF>, except that the buffer
+parameter specifies a scalar variable to use as a buffer. WARNING: A
+variable used as a buffer by C<FileHandle::setvbuf> must not be
+modified in any way until the FileHandle is closed or until
+C<FileHandle::setvbuf> is called again, or memory corruption may
+result!
+
+See L<perlfunc> for complete descriptions of each of the following
+supported C<FileHandle> methods, which are just front ends for the
+corresponding built-in functions:
+
+ close
+ fileno
+ getc
+ gets
+ eof
+ clearerr
+ seek
+ tell
+
+See L<perlvar> for complete descriptions of each of the following
+supported C<FileHandle> methods:
+
+ autoflush
+ output_field_separator
+ output_record_separator
+ input_record_separator
+ input_line_number
+ format_page_number
+ format_lines_per_page
+ format_lines_left
+ format_name
+ format_top_name
+ format_line_break_characters
+ format_formfeed
+
+Furthermore, for doing normal I/O you might need these:
+
+=over
+
+=item $fh->print
+
+See L<perlfunc/print>.
+
+=item $fh->printf
+
+See L<perlfunc/printf>.
+
+=item $fh->getline
+
+This works like <$fh> described in L<perlop/"I/O Operators">
+except that it's more readable and can be safely called in an
+array context but still returns just one line.
+
+=item $fh->getlines
+
+This works like <$fh> when called in an array context to
+read all the remaining lines in a file, except that it's more readable.
+It will also croak() if accidentally called in a scalar context.
+
+=back
+
+=head1 SEE ALSO
+
+The B<IO> extension,
+L<perlfunc>,
+L<perlop/"I/O Operators">.
+
+=cut