Question about I_SENDFD

[Andrey G. Kaplanov]

Respected colleagues! In advanced Unix systems, including SCO UnixWare, SUN OS there is a facility of transmission of descriptor of openning file through stream, by means of the command ioctl I_SENDFD. For instance, following command writes transDsc descriptor to the stream streamDsc.     int ret = ioctl(streamDsc, I_SENDFD, transDsc); On Red Hat Linux kernel 2.2.16 ret is -1,  errno is 22 - Invalid argument. That is here done not so, or be other ways of transmission of file descriptor between processes?     Andrey Kaplanov.