FileHandle - phpMan

NAME
    FileHandle - supply object methods for filehandles

SYNOPSIS
        use FileHandle;

        $fh = FileHandle->new;
        if ($fh->open("< file")) {
            print <$fh>;
            $fh->close;
        }

        $fh = FileHandle->new("> FOO");
        if (defined $fh) {
            print $fh "bar\n";
            $fh->close;
        }

        $fh = FileHandle->new("file", "r");
        if (defined $fh) {
            print <$fh>;
            undef $fh;       # automatically closes the file
        }

        $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;

DESCRIPTION
    NOTE: This class is now a front-end to the IO::* classes.

    "FileHandle::new" creates a "FileHandle", which is a reference to a
    newly created symbol (see the "Symbol" package). If it receives any
    parameters, they are passed to "FileHandle::open"; if the open fails,
    the "FileHandle" object is destroyed. Otherwise, it is returned to the
    caller.

    "FileHandle::new_from_fd" creates a "FileHandle" like "new" does. It
    requires two parameters, which are passed to "FileHandle::fdopen"; if
    the fdopen fails, the "FileHandle" object is destroyed. Otherwise, it is
    returned to the caller.

    "FileHandle::open" accepts one parameter or two. With one parameter, it
    is just a front end for the built-in "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 "FileHandle::open" receives a Perl mode string (">", "+<", etc.) or a
    POSIX fopen() mode string ("w", "r+", etc.), it uses the basic Perl
    "open" operator.

    If "FileHandle::open" is given a numeric mode, it passes that mode and
    the optional permissions value to the Perl "sysopen" operator. For
    convenience, "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.

    "FileHandle::fdopen" is like "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
    "FileHandle::getpos" returns an opaque value that represents the current
    position of the FileHandle, and "FileHandle::setpos" uses that value to
    return to a previously visited position.

    If the C function setvbuf() is available, then "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
    "_IOFBF", "_IOLBF", and "_IONBF", except that the buffer parameter
    specifies a scalar variable to use as a buffer. WARNING: A variable used
    as a buffer by "FileHandle::setvbuf" must not be modified in any way
    until the FileHandle is closed or until "FileHandle::setvbuf" is called
    again, or memory corruption may result!

    See perlfunc for complete descriptions of each of the following
    supported "FileHandle" methods, which are just front ends for the
    corresponding built-in functions:

        close
        fileno
        getc
        gets
        eof
        clearerr
        seek
        tell

    See perlvar for complete descriptions of each of the following supported
    "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:

    $fh->print
        See "print" in perlfunc.

    $fh->printf
        See "printf" in perlfunc.

    $fh->getline
        This works like <$fh> described in "I/O Operators" in perlop except
        that it's more readable and can be safely called in a list context
        but still returns just one line.

    $fh->getlines
        This works like <$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.

    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.

SEE ALSO
    The IO extension, perlfunc, "I/O Operators" in perlop.