...umber socket_fd . It ignores the byte read and only uses the out-of-band auxiliary struct cmsghdr control data, typically supplied by the calling process using CMSG_FIRSTHDR(3) …...ssociated with the open file description on which they are acquired. With fork (2) and/or cmsg (3), multiple processes can share an open file description. So the holder process …...(next) earliest txtime first. It relies on the SO_TXTIME socket option and the SCM_TXTIME CMSG in each packet field to configure the behavior of time dependent sockets: the cloc…