интерфейс сокета Linux (Linux socket interface)
Примечание (Note)
Linux assumes that half of the send/receive buffer is used for
internal kernel structures; thus the values in the corresponding
/proc files are twice what can be observed on the wire.
Linux will allow port reuse only with the SO_REUSEADDR option
when this option was set both in the previous program that
performed a bind(2) to the port and in the program that wants to
reuse the port. This differs from some implementations (e.g.,
FreeBSD) where only the later program needs to set the
SO_REUSEADDR option. Typically this difference is invisible,
since, for example, a server program is designed to always set
this option.
