package FileHandle;
+use 5.006;
+use strict;
+our($VERSION, @ISA, @EXPORT, @EXPORT_OK);
+
+$VERSION = "2.01";
+
+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;
+
+#
+# Some people call "FileHandle::function", so all the functions
+# that were in the old FileHandle class must be imported, too.
+#
+{
+ no strict 'refs';
+
+ my %import = (
+ 'IO::Handle' =>
+ [qw(DESTROY new_from_fd fdopen close fileno getc ungetc gets
+ eof flush error clearerr setbuf setvbuf _open_mode_string)],
+ 'IO::Seekable' =>
+ [qw(seek tell getpos setpos)],
+ 'IO::File' =>
+ [qw(new new_tmpfile open)]
+ );
+ for my $pkg (keys %import) {
+ for my $func (@{$import{$pkg}}) {
+ my $c = *{"${pkg}::$func"}{CODE}
+ or die "${pkg}::$func missing";
+ *$func = $c;
+ }
+ }
+}
+
+#
+# Specialized importer for Fcntl magic.
+#
+sub import {
+ my $pkg = shift;
+ my $callpkg = caller;
+ require Exporter;
+ Exporter::export($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);
+}
+
+# Rebless standard file handles
+bless *STDIN{IO}, "FileHandle" if ref *STDIN{IO} eq "IO::Handle";
+bless *STDOUT{IO}, "FileHandle" if ref *STDOUT{IO} eq "IO::Handle";
+bless *STDERR{IO}, "FileHandle" if ref *STDERR{IO} eq "IO::Handle";
+
+1;
+
+__END__
+
=head1 NAME
FileHandle - supply object methods for filehandles
use FileHandle;
- $fh = new FileHandle;
- if ($fh->open "< file") {
+ $fh = FileHandle->new;
+ if ($fh->open("< file")) {
print <$fh>;
$fh->close;
}
- $fh = new FileHandle "> FOO";
+ $fh = FileHandle->new("> FOO");
if (defined $fh) {
print $fh "bar\n";
$fh->close;
}
- $fh = new FileHandle "file", "r";
+ $fh = FileHandle->new("file", "r");
if (defined $fh) {
print <$fh>;
undef $fh; # automatically closes the file
}
- $fh = new FileHandle "file", O_WRONLY|O_APPEND;
+ $fh = FileHandle->new("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,
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 in either Perl form (">", "+<", etc.) or POSIX form
-("w", "r+", etc.).
+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
Furthermore, for doing normal I/O you might need these:
-=over
+=over 4
=item $fh->print
=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.
+except that it's more readable and can be safely called in a
+list context but still returns just one line.
=item $fh->getlines
-This works like <$fh> when called in an array context to
+This works like <$fh> when called in a list context to
read all the remaining lines in a file, except that it's more readable.
It will also croak() if accidentally called in a scalar context.
=back
+There are many other functions available since FileHandle is descended
+from IO::File, IO::Seekable, and IO::Handle. Please see those
+respective pages for documentation on more functions.
+
=head1 SEE ALSO
+The B<IO> extension,
L<perlfunc>,
-L<perlop/"I/O Operators">,
-L<POSIX/"FileHandle">
-
-=head1 BUGS
-
-Due to backwards compatibility, all filehandles resemble objects
-of class C<FileHandle>, or actually classes derived from that class.
-They actually aren't. Which means you can't derive your own
-class from C<FileHandle> and inherit those methods.
+L<perlop/"I/O Operators">.
=cut
-
-require 5.000;
-use Carp;
-use Fcntl;
-use Symbol;
-use English;
-use SelectSaver;
-
-require Exporter;
-require DynaLoader;
-@ISA = qw(Exporter DynaLoader);
-
-@EXPORT = (@Fcntl::EXPORT,
- qw(_IOFBF _IOLBF _IONBF));
-
-@EXPORT_OK = qw(
- autoflush
- output_field_separator
- output_record_separator
- input_record_separator
- input_line_number
- format_page_number
- format_lines_per_page
- format_lines_left
- format_name
- format_top_name
- format_line_break_characters
- format_formfeed
-
- print
- printf
- getline
- getlines
-);
-
-
-################################################
-## Interaction with the XS.
-##
-
-bootstrap FileHandle;
-
-sub AUTOLOAD {
- if ($AUTOLOAD =~ /::(_?[a-z])/) {
- $AutoLoader::AUTOLOAD = $AUTOLOAD;
- goto &AutoLoader::AUTOLOAD
- }
- my $constname = $AUTOLOAD;
- $constname =~ s/.*:://;
- my $val = constant($constname);
- defined $val or croak "$constname is not a valid FileHandle macro";
- *$AUTOLOAD = sub { $val };
- goto &$AUTOLOAD;
-}
-
-
-################################################
-## Constructors, destructors.
-##
-
-sub new {
- @_ >= 1 && @_ <= 3 or croak 'usage: new FileHandle [FILENAME [,MODE]]';
- my $class = shift;
- my $fh = gensym;
- if (@_) {
- FileHandle::open($fh, @_)
- or return undef;
- }
- bless $fh, $class;
-}
-
-sub new_from_fd {
- @_ == 3 or croak 'usage: new_from_fd FileHandle FD, MODE';
- my $class = shift;
- my $fh = gensym;
- FileHandle::fdopen($fh, @_)
- or return undef;
- bless $fh, $class;
-}
-
-sub DESTROY {
- my ($fh) = @_;
- close($fh);
-}
-
-################################################
-## Open and close.
-##
-
-sub pipe {
- @_ and croak 'usage: FileHandle::pipe()';
- my $readfh = new FileHandle;
- my $writefh = new FileHandle;
- pipe($readfh, $writefh)
- or return undef;
- ($readfh, $writefh);
-}
-
-sub _open_mode_string {
- my ($mode) = @_;
- $mode =~ /^\+?(<|>>?)$/
- or $mode =~ s/^r(\+?)$/$1</
- or $mode =~ s/^w(\+?)$/$1>/
- or $mode =~ s/^a(\+?)$/$1>>/
- or croak "FileHandle: bad open mode: $mode";
- $mode;
-}
-
-sub open {
- @_ >= 2 && @_ <= 4 or croak 'usage: $fh->open(FILENAME [,MODE [,PERMS]])';
- my ($fh, $file) = @_;
- if (@_ > 2) {
- my ($mode, $perms) = @_[2, 3];
- if ($mode =~ /^\d+$/) {
- defined $perms or $perms = 0666;
- return sysopen($fh, $file, $mode, $perms);
- }
- $file = "./" . $file unless $file =~ m#^/#;
- $file = _open_mode_string($mode) . " $file\0";
- }
- open($fh, $file);
-}
-
-sub fdopen {
- @_ == 3 or croak 'usage: $fh->fdopen(FD, MODE)';
- my ($fh, $fd, $mode) = @_;
- if (ref($fd) =~ /GLOB\(/) {
- # It's a glob reference; remove the star from its name.
- ($fd = "".$$fd) =~ s/^\*//;
- } elsif ($fd =~ m#^\d+$#) {
- # It's an FD number; prefix with "=".
- $fd = "=$fd";
- }
- open($fh, _open_mode_string($mode) . '&' . $fd);
-}
-
-sub close {
- @_ == 1 or croak 'usage: $fh->close()';
- close($_[0]);
-}
-
-################################################
-## Normal I/O functions.
-##
-
-sub fileno {
- @_ == 1 or croak 'usage: $fh->fileno()';
- fileno($_[0]);
-}
-
-sub getc {
- @_ == 1 or croak 'usage: $fh->getc()';
- getc($_[0]);
-}
-
-sub gets {
- @_ == 1 or croak 'usage: $fh->gets()';
- my ($handle) = @_;
- scalar <$handle>;
-}
-
-sub eof {
- @_ == 1 or croak 'usage: $fh->eof()';
- eof($_[0]);
-}
-
-sub clearerr {
- @_ == 1 or croak 'usage: $fh->clearerr()';
- seek($_[0], 0, 1);
-}
-
-sub seek {
- @_ == 3 or croak 'usage: $fh->seek(POS, WHENCE)';
- seek($_[0], $_[1], $_[2]);
-}
-
-sub tell {
- @_ == 1 or croak 'usage: $fh->tell()';
- tell($_[0]);
-}
-
-sub print {
- @_ or croak 'usage: $fh->print([ARGS])';
- my $this = shift;
- print $this @_;
-}
-
-sub printf {
- @_ or croak 'usage: $fh->printf([ARGS])';
- my $this = shift;
- printf $this @_;
-}
-
-sub getline {
- @_ == 1 or croak 'usage: $fh->getline';
- my $this = shift;
- return scalar <$this>;
-}
-
-sub getlines {
- @_ == 1 or croak 'usage: $fh->getline()';
- my $this = shift;
- wantarray or croak "Can't call FileHandle::getlines in a scalar context";
- return <$this>;
-}
-
-################################################
-## State modification functions.
-##
-
-sub autoflush {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $OUTPUT_AUTOFLUSH;
- $OUTPUT_AUTOFLUSH = @_ > 1 ? $_[1] : 1;
- $prev;
-}
-
-sub output_field_separator {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $OUTPUT_FIELD_SEPARATOR;
- $OUTPUT_FIELD_SEPARATOR = $_[1] if @_ > 1;
- $prev;
-}
-
-sub output_record_separator {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $OUTPUT_RECORD_SEPARATOR;
- $OUTPUT_RECORD_SEPARATOR = $_[1] if @_ > 1;
- $prev;
-}
-
-sub input_record_separator {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $INPUT_RECORD_SEPARATOR;
- $INPUT_RECORD_SEPARATOR = $_[1] if @_ > 1;
- $prev;
-}
-
-sub input_line_number {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $INPUT_LINE_NUMBER;
- $INPUT_LINE_NUMBER = $_[1] if @_ > 1;
- $prev;
-}
-
-sub format_page_number {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_PAGE_NUMBER;
- $FORMAT_PAGE_NUMBER = $_[1] if @_ > 1;
- $prev;
-}
-
-sub format_lines_per_page {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_LINES_PER_PAGE;
- $FORMAT_LINES_PER_PAGE = $_[1] if @_ > 1;
- $prev;
-}
-
-sub format_lines_left {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_LINES_LEFT;
- $FORMAT_LINES_LEFT = $_[1] if @_ > 1;
- $prev;
-}
-
-sub format_name {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_NAME;
- $FORMAT_NAME = qualify($_[1], caller) if @_ > 1;
- $prev;
-}
-
-sub format_top_name {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_TOP_NAME;
- $FORMAT_TOP_NAME = qualify($_[1], caller) if @_ > 1;
- $prev;
-}
-
-sub format_line_break_characters {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_LINE_BREAK_CHARACTERS;
- $FORMAT_LINE_BREAK_CHARACTERS = $_[1] if @_ > 1;
- $prev;
-}
-
-sub format_formfeed {
- my $old = new SelectSaver qualify($_[0], caller);
- my $prev = $FORMAT_FORMFEED;
- $FORMAT_FORMFEED = $_[1] if @_ > 1;
- $prev;
-}
-
-1;