Swift “UDP Read” code - unsaferawbufferpointer compile error - swift

Question

I’m sure someone can solve this in seconds but I’m very new to swift, using playgrounds on the iPad. I’m trying to modify some SendUDP code to recieve instead, but I can’t solve the compile error (unsafepointer is not convertible to unsaferawbufferpointer) on the readResult= line. The SEND works fine with very similar code, but I’m really struggling here, way out of my depth...
Here’s the code
func readUDP() {
guard
let addresses =
try ? addressesFor(host: "192.168.4.1", port: 80)
else {
print("host not found")
return
}
if addresses.count != 1 {
print("host ambiguous; using the first one")
}
address = addresses[0]
fd1 = socket(Int32(address.ss_family), SOCK_DGRAM, 0)
guard fd1 >= 0
else {
print("`socket` failed`")
return
}
defer {
let junk = close(fd1)
assert(junk == 0)
}
var message = [UInt8](repeating: 0, count: 1024)
let messageCount = message.count
var readResult = message.withUnsafeBytes {
(messagePtr: UnsafePointer < UInt8 > ) - > Int in
return address.withSockAddr {
(sa, saLen) - > Int in
return recvfrom(fd1, messagePtr, messageCount, 0, sa, & saLen)
}
}
guard readResult >= 0
else {
print("read failed")
return
}
print("success")
}

Answer 1

You can use Swift's implicit bridging to simplify to something like this:
var message = [UInt8](repeating: 0, count: 1024)
let messageCount = message.count
var readResult = address.withSockAddr {
(sa, saLen) - > Int in
return recvfrom(fd1, &message, messageCount, 0, sa, &saLen)
}
guard readResult >= 0
else {
print("read failed")
return
}