unix: the error should not be overridden by anyToSockaddr

[Asutorufa]

The error should not be overridden by anyToSockaddr. Otherwise, the
length of the data will return as -1

Upon successful completion, recvmsg() shall return the length of the
message in bytes. If no messages are available to be received and
the peer has performed an orderly shutdown, recvmsg() shall return
0. Otherwise, -1 shall be returned and
https://man7.org/linux/man-pages/man3/errno.3.html set to indicate
the error.

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Patch Set 1:

(1 comment)

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