warn "Jo is noch offen" if fileno *HANDLE;

Quote

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;