Comment by vbezhenar a day ago
ICMP is just different protocol from UDP. There's field "Protocol" in IP packet. 0x01 = ICMP, 0x06 = TCP, 0x11 = UDP.
I think that this article gets terminology wrong. It's not UDP socket that gets created here, but Datagram socket. Seems to be bad API naming in Rust library.
To give a more nuanced reply versus the "you're wrong" ones already here, the difference is that UDP adds send and receive ports, enabling most modern users (& uses) of UDP. Hence, it is the "User" datagram protocol.
(it also adds a checksum, which used to be more important than it is nowadays, but still well worth it imho.)
In related news, all rectangles are squares and all animals are dogs.
Let me rephrase GP into (I hope) a more useful analogy. — actually, here’s the whole analogous exchange:
“A rectangle is an equal-sided rectangle (i.e. “square”) though. That’s what the R stands for.”
“No? Why would you think a rectangle is a square?”
Just as not all rectangles are squares (squares are a specific subset of rectangles), not all datagram protocols are UDP (UDP is just one particular datagram protocol).
> It's not UDP socket that gets created here, but Datagram socket
A datagram socket is a UDP socket, though. That's what the D stands for.