i'm running into a bit of an issue with this little chunk of code.

    open($fhname, "+<$devname") || die "cannot open serial device $dev
+name $!\n";
    $device->{fd} =  fileno($fhname);
    select((select($fhname), $| = 1)[0]);
    print STDOUT "it got selected\n";

    $fd  = fileno($fhname);
    $tio = new POSIX::Termios;
    $tio->setispeed(B38400);
    $tio->setospeed(B38400);
    $tio->setiflag(IGNBRK|IGNPAR);
    $tio->setoflag(0);
    $tio->setlflag(0);
    $tio->setcflag(CS8|CLOCAL|CREAD|B38400);
    for (0 .. 16) { $tio->setcc($_, 0); }
    $tio->setcc(VMIN,  1);
    $tio->setcc(VTIME, 1);
    $tio->setattr($fd) || warn "Can't set attributes on $devname: $!\n
+";
[download]

the problem arrises when moving it to one specific machine. it works flawlessly on all but one. the version of perl is slightly different (rpm packs 5.6.0-12, *-17). works on 12 not 17.

strace keeps hanging on the open

open("/dev/modem", O_RDWR
(hangs til TERM)

any ideas?