Полезная информация


IO::File - supply object methods for filehandles


    use IO::File;

    $fh = new IO::File;
    if ($fh->open("< file")) {
        print <$fh>;

    $fh = new IO::File "> file";
    if (defined $fh) {
        print $fh "bar\n";

    $fh = new IO::File "file", "r";
    if (defined $fh) {
        print <$fh>;
        undef $fh;       # automatically closes the file

    $fh = new IO::File "file", O_WRONLY|O_APPEND;
    if (defined $fh) {
        print $fh "corge\n";

        $pos = $fh->getpos;

        undef $fh;       # automatically closes the file

    autoflush STDOUT 1;


IO::File inherits from IO::Handle and IO::Seekable. It extends these classes with methods that are specific to file handles.


new ([ ARGS ] )

Creates a IO::File. If it receives any parameters, they are passed to the method open; if the open fails, the object is destroyed. Otherwise, it is returned to the caller.


Creates an IO::File opened for read/write on a newly created temporary file. On systems where this is possible, the temporary file is anonymous (i.e. it is unlinked after creation, but held open). If the temporary file cannot be created or opened, the IO::File object is destroyed. Otherwise, it is returned to the caller.



open accepts one, two or three parameters. 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 IO::File::open receives a Perl mode string (``>'', ``+<'', etc.) or a POSIX fopen() mode string (``w'', ``r+'', etc.), it uses the basic Perl open operator.

If IO::File::open is given a numeric mode, it passes that mode and the optional permissions value to the Perl sysopen operator. For convenience, IO::File::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 IO::File will still work.


the perlfunc manpage, I/O Operators, Handle Seekable


Derived from FileHandle.pm by Graham Barr <bodg@tiuk.ti.com>.


We are painfully aware that these documents may contain incorrect links and misformatted HTML. Such bugs lie in the automatic translation process that automatically created the hundreds and hundreds of separate documents that you find here. Please do not report link or formatting bugs, because we cannot fix per-document problems. The only bug reports that will help us are those that supply working patches to the installhtml or pod2html programs, or to the Pod::HTML module itself, for which I and the entire Perl community will shower you with thanks and praises.

If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.

--Tom Christiansen, Perl Documentation Compiler and Editor

Return to the Perl Documentation Index.
Return to the Perl Home Page.