unix_rights

        # Socket::AncillaryData.unix_rights

(from ruby core)
### Implementation from AncillaryData
---
    Socket::AncillaryData.unix_rights(io1, io2, ...) => ancillarydata

---

Creates a new Socket::AncillaryData object which contains file
descriptors as data.

    p Socket::AncillaryData.unix_rights(STDERR)
    #=> #<Socket::AncillaryData: UNIX SOCKET RIGHTS 2>


(from ruby core)
### Implementation from AncillaryData
---
    ancillarydata.unix_rights => array-of-IOs or nil

---

returns the array of IO objects for SCM_RIGHTS control message in UNIX
domain socket.

The class of the IO objects in the array is IO or Socket.

The array is attached to *ancillarydata* when it is instantiated. For
example, BasicSocket#recvmsg attach the array when receives a SCM_RIGHTS
control message and :scm_rights=>true option is given.

    # recvmsg needs :scm_rights=>true for unix_rights
    s1, s2 = UNIXSocket.pair
    p s1                                         #=> #<UNIXSocket:fd 3>
    s1.sendmsg "stdin and a socket", 0, nil, Socket::AncillaryData.unix_rights(STDIN, s1)
    _, _, _, ctl = s2.recvmsg(:scm_rights=>true)
    p ctl                                        #=> #<Socket::AncillaryData: UNIX SOCKET RIGHTS 6 7>
    p ctl.unix_rights                            #=> [#<IO:fd 6>, #<Socket:fd 7>]
    p File.identical?(STDIN, ctl.unix_rights[0]) #=> true
    p File.identical?(s1, ctl.unix_rights[1])    #=> true

    # If :scm_rights=>true is not given, unix_rights returns nil
    s1, s2 = UNIXSocket.pair
    s1.sendmsg "stdin and a socket", 0, nil, Socket::AncillaryData.unix_rights(STDIN, s1)
    _, _, _, ctl = s2.recvmsg
    p ctl #=> #<Socket::AncillaryData: UNIX SOCKET RIGHTS 6 7>
    p ctl.unix_rights #=> nil