>Process is not a file because you cannot send signals to a file https://man7.org/linux/man-pages/man2/pidfd_send_signal.2.html https://man7.org/linux/man-page

>Process is not a file because you cannot send signals to a file https://man7.org/linux/man-pages/man2/pidfd_send_signal.2.html https://man7.org/linux/man-pages/man2/pidfd_send_signal.2.ht... Also sockets have the concept of ancillary channels used to deliver out of band data (see recvmsg). If every system resource had such channel, it could be used for control similar to how sockets do it.