General:
Forums subtopic: App & System Services > Networking
TN3151 Choosing the right networking API
Networking Overview document — Despite the fact that this is in the archive, this is still really useful.
TLS for App Developers forums post
Choosing a Network Debugging Tool documentation
WWDC 2019 Session 712 Advances in Networking, Part 1 — This explains the concept of constrained networking, which is Apple’s preferred solution to questions like How do I check whether I’m on Wi-Fi?
TN3135 Low-level networking on watchOS
TN3179 Understanding local network privacy
Adapt to changing network conditions tech talk
Understanding Also-Ran Connections forums post
Extra-ordinary Networking forums post
Foundation networking:
Forums tags: Foundation, CFNetwork
URL Loading System documentation — NSURLSession, or URLSession in Swift, is the recommended API for HTTP[S] on Apple platforms.
Moving to Fewer, Larger Transfers forums post
Testing Background Session Code forums post
Network framework:
Forums tag: Network
Network framework documentation — Network framework is the recommended API for TCP, UDP, and QUIC on Apple platforms.
Building a custom peer-to-peer protocol sample code (aka TicTacToe)
Implementing netcat with Network Framework sample code (aka nwcat)
Configuring a Wi-Fi accessory to join a network sample code
Moving from Multipeer Connectivity to Network Framework forums post
NWEndpoint History and Advice forums post
Network Extension (including Wi-Fi on iOS):
See Network Extension Resources
Wi-Fi Fundamentals
TN3111 iOS Wi-Fi API overview
Wi-Fi Aware framework documentation
Wi-Fi on macOS:
Forums tag: Core WLAN
Core WLAN framework documentation
Wi-Fi Fundamentals
Secure networking:
Forums tags: Security
Apple Platform Security support document
Preventing Insecure Network Connections documentation — This is all about App Transport Security (ATS).
WWDC 2017 Session 701 Your Apps and Evolving Network Security Standards [1] — This is generally interesting, but the section starting at 17:40 is, AFAIK, the best information from Apple about how certificate revocation works on modern systems.
Available trusted root certificates for Apple operating systems support article
Requirements for trusted certificates in iOS 13 and macOS 10.15 support article
About upcoming limits on trusted certificates support article
Apple’s Certificate Transparency policy support article
What’s new for enterprise in iOS 18 support article — This discusses new key usage requirements.
Technote 2232 HTTPS Server Trust Evaluation
Technote 2326 Creating Certificates for TLS Testing
QA1948 HTTPS and Test Servers
Miscellaneous:
More network-related forums tags: 5G, QUIC, Bonjour
On FTP forums post
Using the Multicast Networking Additional Capability forums post
Investigating Network Latency Problems forums post
WirelessInsights framework documentation
iOS Network Signal Strength forums post
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
[1] This video is no longer available from Apple, but the URL should help you locate other sources of this info.
Networking
RSS for tagExplore the networking protocols and technologies used by the device to connect to Wi-Fi networks, Bluetooth devices, and cellular data services.
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I am currently developing a custom-protocol VPN application for iOS using PacketTunnelProvider. I have also integrated an HTTP proxy service, which is launched via a dylib.
The overall flow is as follows:
App -> VPN TUN -> Local HTTP Proxy -> External Network
I have a question:
I am capturing all traffic, and normally, requests sent out by the HTTP proxy are also captured again by the VPN. However, when I send requests using createUdpSession in my code, they are not being captured by the virtual interface (TUN).
What could be the reason for this?
override func startTunnel(options: [String : NSObject]?, completionHandler: @escaping (Error?) -> Void) {
let tunnelNetworkSettings = NEPacketTunnelNetworkSettings(tunnelRemoteAddress: "192.168.18.0")
tunnelNetworkSettings.mtu=1400
let ipv4Settings = NEIPv4Settings(addresses: ["192.169.10.10"], subnetMasks: ["255.255.255.0"])
ipv4Settings.includedRoutes=[NEIPv4Route.default()]
ipv4Settings.excludedRoutes = [NEIPv4Route(destinationAddress: "10.0.0.0", subnetMask: "255.0.0.0"),
NEIPv4Route(destinationAddress: "172.16.0.0", subnetMask: "255.240.0.0"),
NEIPv4Route(destinationAddress: "192.168.0.0", subnetMask: "255.255.0.0"),
NEIPv4Route(destinationAddress:"127.0.0.0", subnetMask: "255.0.0.0"),
]
tunnelNetworkSettings.ipv4Settings = ipv4Settings
// Configure proxy settings
let proxySettings = NEProxySettings()
proxySettings.httpEnabled = true
proxySettings.httpServer = NEProxyServer(address: "127.0.0.1", port: 7890)
proxySettings.httpsEnabled = true
proxySettings.httpsServer = NEProxyServer(address: "127.0.0.1", port: 7890)
proxySettings.excludeSimpleHostnames = true
proxySettings.exceptionList=["localhost","127.0.0.1"]
tunnelNetworkSettings.proxySettings = proxySettings
setTunnelNetworkSettings(tunnelNetworkSettings) { [weak self] error in
if error != nil {
completionHandler(error)
return
}
completionHandler(nil)
let stack = TUNInterface(packetFlow: self!.packetFlow)
RawScoketFactory.TunnelProvider=self
stack.register(stack: UDPDirectStack())
stack.register(stack: TCPDirectStack())
stack.start()
}
}
NWUdpSession.swift
//
// NWUDPSocket.swift
// supervpn
//
// Created by TobbyQuinn on 2025/2/3.
//
import Foundation
import NetworkExtension
import CocoaLumberjack
public protocol NWUDPSocketDelegate: AnyObject{
func didReceive(data:Data,from:NWUDPSocket)
func didCancel(socket:NWUDPSocket)
}
public class NWUDPSocket:NSObject{
private let session:NWUDPSession
private let timeout:Int
private var pendingWriteData: [Data] = []
private var writing = false
private let queue:DispatchQueue=QueueFactory.getQueue()
public weak var delegate:NWUDPSocketDelegate?
public init?(host:String,port:UInt16,timeout:Int=Opt.UDPSocketActiveTimeout){
guard let udpSession = RawScoketFactory.TunnelProvider?.createUDPSession(to: NWHostEndpoint(hostname: host, port: "\(port)"), from: nil) else{
return nil
}
session = udpSession
self.timeout=timeout
super.init()
session.addObserver(self, forKeyPath: #keyPath(NWUDPSession.state),options: [.new], context: nil)
session.setReadHandler({ dataArray, error in
self.queueCall{
guard error == nil, let dataArray = dataArray else {
print("Error when reading from remote server or connection reset")
return
}
for data in dataArray{
self.delegate?.didReceive(data: data, from: self)
}
}
}, maxDatagrams: 32)
}
/**
Send data to remote.
- parameter data: The data to send.
*/
public func write(data: Data) {
pendingWriteData.append(data)
checkWrite()
}
public func disconnect() {
session.cancel()
}
public override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
guard keyPath == "state" else {
return
}
switch session.state {
case .cancelled:
queueCall {
self.delegate?.didCancel(socket: self)
}
case .ready:
checkWrite()
default:
break
}
}
private func checkWrite() {
guard session.state == .ready else {
return
}
guard !writing else {
return
}
guard pendingWriteData.count > 0 else {
return
}
writing = true
session.writeMultipleDatagrams(self.pendingWriteData) {_ in
self.queueCall {
self.writing = false
self.checkWrite()
}
}
self.pendingWriteData.removeAll(keepingCapacity: true)
}
private func queueCall(block:@escaping ()->Void){
queue.async {
block()
}
}
deinit{
session.removeObserver(self, forKeyPath: #keyPath(NWUDPSession.state))
}
}
I’m developing an app designed for hospital environments, where public internet access may not be available. The app includes two components: the main app and a Local Connectivity Extension. Both rely on persistent TCP socket connections to communicate with a local server.
We’re observing a recurring issue where the extension’s socket becomes unresponsive every 1–3 hours, but only when the device is on the lock screen, even if the main app remains in the foreground.
When the screen is not locked, the connection is stable and no disconnections occur.
❗ Issue Details:
• What’s going on: The extension sends a keep-alive ping packet every second, and the server replies with a pong and a system time packet.
• The bug: The server stops receiving keep alive packets from the extension.
• On the server, we detect about 30 second gap on the server, a gap that shows no packets were received by the extension. This was confirmed via server logs and Wireshark).
• On the extension, from our logs there was no gap in sending packets. From it’s perspective, all packets were sent with no error.
• Because no packet are being received by the server, no packets will be sent to the extension. Eventually the server closes the connection due to keep-alive timeout.
• FYI we log when the NEAppPushProvider subclass sleeps and it did NOT go to sleep while we were debugging.
🧾 Example Logs:
Extension log:
2025-03-24 18:34:48.808 sendKeepAliveRequest()
2025-03-24 18:34:49.717 sendKeepAliveRequest()
2025-03-24 18:34:50.692 sendKeepAliveRequest()
... // continuous sending of the ping packet to the server, no problems here
2025-03-24 18:35:55.063 sendKeepAliveRequest()
2025-03-24 18:35:55.063 keepAliveTimer IS TIME OUT... in CoreService. // this is triggered because we did not receive any packets from the server
2025-03-24 18:34:16.298 No keep-alive received for 16 seconds... connection ID=95b3... // this shows that there has been no packets being received by the extension
...
2025-03-24 18:34:30.298 Connection timed out on keep-alive. connection ID=95b3... // eventually closes due to no packets being received
2025-03-24 18:34:30.298 Remote Subsystem Disconnected {name=iPhone|Replica-Ext|...}
✅ Observations:
• The extension process continues running and logging keep-alive attempts.
• However, network traffic stops reaching the server, and no inbound packets are received by the extension.
• It looks like the socket becomes silently suspended or frozen, without being properly closed or throwing an error.
❓Questions:
• Do you know why this might happen within a Local Connectivity Extension, especially under foreground conditions and locked ?
• Is there any known system behavior that might cause the socket to be suspended or blocked in this way after running for a few hours?
Any insights or recommendations would be greatly appreciated.
Thank you!
I had noticed that my slaac address changed between one beta and the other, but wasn't sure. Now with the RC 15.4 RC (24E247) I made point of preserving the info before updating from the previous beta.
What I noticed is that not only the slaac address changes, but also the my ether address, even though I have it on Fixed in the settings.
Is it expected that the ether, and the slaac, not be rotated after a OS update?
Topic:
App & System Services
SubTopic:
Networking
Apple multi-peer with 12 devices is unstable. Dear All,
Has anyone tried Apple multi-peer with 12 devices connected? We are building an application relying on multi-peer where 12 Ipads will be updating data and each device needs to share data between. Can anyone tell me if we can use multi-peer framework for connecting 12 devices in the multi-peer network? We are facing stability problems in the connection when we connect 12 devices in the network.
In order to create a Message Filter Extension it is necessary to set up Shared Web Credentials.
I'd like to form an understanding of what role SWC plays when the OS is making request to the associated network service (when the extension has called deferQueryRequestToNetwork()) and how this differs from when an app directly uses Shared Web Credentials itself.
When an app is making direct use of SWC, it makes a request to obtain the user's credentials from the web site.
However in the case of a Message Filter Extension, there aren't any individual user credentials, so what is happening behind the scenes when the OS makes a server request on behalf of a Message Filtering Extension?
A more general question - the documentation for Shared Web Credentials says "Associated domains establish a secure association between domains and your app.".
Thank you
Topic:
App & System Services
SubTopic:
Networking
Tags:
iOS
SMS and Call Reporting
Authentication Services
What is the best way to detect if the Wifi is being used for Wireless Carplay or is just a normal network interface?
This is just an FYI in case someone else runs into this problem.
This afternoon (12 Dec 2025), I updated to macOS 26.2 and lost my network.
The System Settings' Wi-Fi light was green and said it was connected, but traceroute showed "No route to host".
I turned Wi-Fi on & off.
I rebooted the Mac.
I rebooted the eero network.
I switched to tethering to my iPhone.
I switched to physical ethernet cable.
Nothing worked.
Then I remembered I had a beta of an app with a network system extension that was distributed through TestFlight.
I deleted the app, and networking came right back.
I had this same problem ~2 years ago. Same story:
app with network system extension + TestFlight + macOS update = lost network.
(My TestFlight build might have expired, but I'm not certain)
I don't know if anyone else has had this problem, but I thought I'd share this in case it helps.
How often do we see control filter start and stop?
I read somewhere that data filter is long lived and control Filter is short lived.
When does the operating system kills the control filter process?
Hello, I'm working on a Transparent Proxy and when the proxy is being stopped, I'm stopping all the flows by calling
flow.closeWriteWithError(POSIXError(.ECANCELED))
flow.closeReadWithError(POSIXError(.ECANCELED))
Then all the flows are deallocated.
When deallocating the flow the crash occurs:
OS Version: macOS 14.1.2 (23B92)
Exception Type: EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x0000000000000001, 0x000000018c2ef704
Termination Reason: Namespace SIGNAL, Code 5 Trace/BPT trap: 5
Terminating Process: exc handler [553]
Thread 32 Crashed:: Dispatch queue: <my dispatch queue>
0 CoreFoundation 0x18c2ef704 CF_IS_OBJC + 76
1 CoreFoundation 0x18c23f61c CFErrorGetDomain + 32
2 libnetworkextension.dylib 0x19fe56a00 flow_error_to_errno + 28
3 libnetworkextension.dylib 0x19fe56920 flow_handle_pending_write_requests + 216
4 libnetworkextension.dylib 0x19fe5667c __NEFlowDeallocate + 380
5 CoreFoundation 0x18c2efe28 _CFRelease + 292
6 NetworkExtension 0x19d208390 -[NEAppProxyFlow dealloc] + 36
Is there any way to debug what is happening and if it's related to closing the flow with POSIXError?
Thank you
Starting in iOS 26, two notable changes have been made to CallKit, LiveCommunicationKit, and the PushToTalk framework:
As a diagnostic aid, we're introducing new dialogs to warn apps of voip push related issue, for example when they fail to report a call or when when voip push delivery stops. The specific details of that behavior are still being determined and are likely to change over time, however, the critical point here is that these alerts are only intended to help developers debug and improve their app. Because of that, they're specifically tied to development and TestFlight signed builds, so the alert dialogs will not appear for customers running app store builds. The existing termination/crashes will still occur, but the new warning alerts will not appear.
As PushToTalk developers have previously been warned, the last unrestricted PushKit entitlement ("com.apple.developer.pushkit.unrestricted-voip.ptt") has been disabled in the iOS 26 SDK. ALL apps that link against the iOS 26 SDK which receive a voip push through PushKit and which fail to report a call to CallKit will be now be terminated by the system, as the API contract has long specified.
__
Kevin Elliott
DTS Engineer, CoreOS/Hardware
Here's a simple program that spoofs an ARP reply for a given IP address. If I spin up two terminal sessions on the same machine.
Run this code in one window
% ./spoof en0 192.168.1.7
Listening on en0 for ARP requests to 192.168.1.7
Spoofing MAC: 00:0c:87:47:50:27
And in the second window cause the OS to issue an ARP_REQ
% ping 192.168.1.7
You will see the program respond to the ARP request. (Wireshark will see the ARP_REQ and ARP_REPLY packets) however my arp table isn't updated with the MAC for the IP address. There is no firewall active.
% arp -a|grep 192.168.1.7
(192.168.1.7) at (incomplete) on en0 ifscope [ethernet]
This is running on a MacBook pro M3 (OSX 15.4).
HOWEVER, on a MacBook pro M4 (OSX 15.2) is does Work !!!!!
Can anyone explain why its not working?
spoof.txt
I'm using NERelayManager to set Relay configuration which all works perfectly fine.
I then do a curl with the included domain and while I see QUIC connection succeeds with relay server and H3 request goes to the server, the connection gets abruptly closed by the client with "Software caused connection abort".
Console has this information:
default 09:43:04.459517-0700 curl nw_flow_connected [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] Transport protocol connected (quic)
default 09:43:04.459901-0700 curl [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] event: flow:finish_transport @0.131s
default 09:43:04.460745-0700 curl nw_flow_connected [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] Joined protocol connected (http3)
default 09:43:04.461049-0700 curl [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] event: flow:finish_transport @0.133s
default 09:43:04.465115-0700 curl [C2 E47A3A0C-7275-4F6B-AEDF-59077ABAE34B 192.168.4.197:4433 quic, multipath service: 1, tls, definite, attribution: developer] cancel
default 09:43:04.465238-0700 curl [C2 E47A3A0C-7275-4F6B-AEDF-59077ABAE34B 192.168.4.197:4433 quic, multipath service: 1, tls, definite, attribution: developer] cancelled
[C2 FCB1CFD1-4BF9-4E37-810E-81265D141087 192.168.4.139:53898<->192.168.4.197:4433]
Connected Path: satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi
Duration: 0.121s, QUIC @0.000s took 0.000s, TLS 1.3 took 0.111s
bytes in/out: 2880/4322, packets in/out: 4/8, rtt: 0.074s, retransmitted bytes: 0, out-of-order bytes: 0
ecn packets sent/acked/marked/lost: 3/1/0/0
default 09:43:04.465975-0700 curl nw_flow_disconnected [C2 192.168.4.197:4433 cancelled multipath-socket-flow ((null))] Output protocol disconnected
default 09:43:04.469189-0700 curl nw_endpoint_proxy_receive_report [C1.1 IPv4#124bdc4d:80 in_progress proxy (satisfied (Path is satisfied), interface: en0[802.11], ipv4, ipv6, dns, proxy, uses wifi)] Privacy proxy failed with error 53 ([C1.1.1] masque Proxy: http://192.168.4.197:4433)
default 09:43:04.469289-0700 curl [C1.1.1 192.168.4.197:4433 failed socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] event: flow:failed_connect @0.141s, error Software caused connection abort
Relay server otherwise works fine with our QUIC MASQUE clients but not with built-in macOS MASQUE client. Anything I'm missing?
I need to run multiple, slightly different copies of a modeling tool, which all need access to a model repository on a different machine. Security Settings -> Network tends to pick one modeling tool (and unfortunately the wrong one) for permission, but the dialog offers no way to add the other copies manually. Where can I configure the permission on low level.
[macOS Sequoia 15.6.1]
Topic:
App & System Services
SubTopic:
Networking
From time to time the subject of NECP grows up, both here on DevForums and in DTS cases. I’ve posted about this before but I wanted to collect those tidbits into single coherent post.
If you have questions or comments, start a new thread in the App & System Services > Networking subtopic and tag it with Network Extension. That way I’ll be sure to see it go by.
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
A Peek Behind the NECP Curtain
NECP stands for Network Extension Control Protocol. It’s a subsystem within the Apple networking stack that controls which programs have access to which network interfaces. It’s vitally important to the Network Extension subsystem, hence the name, but it’s used in many different places. Indeed, a very familiar example of its use is the Settings > Mobile Data [1] user interface on iOS.
NECP has no explicit API, although there are APIs that are offer some insight into its state. Continuing the Settings > Mobile Data example above, there is a little-known API, CTCellularData in the Core Telephony framework, that returns whether your app has access to WWAN.
Despite having no API, NECP is still relevant to developers. The Settings > Mobile Data example is one place where it affects app developers but it’s most important for Network Extension (NE) developers. A key use case for NECP is to prevent VPN loops. When starting an NE provider, the system configures the NECP policy for the NE provider’s process to prevent it from using a VPN interface. This means that you can safely open a network connection inside your VPN provider without having to worry about its traffic being accidentally routed back to you. This is why, for example, an NE packet tunnel provider can use any networking API it wants, including BSD Sockets, to run its connection without fear of creating a VPN loop [1].
One place that NECP shows up regularly is the system log. Next time you see a system log entry like this:
type: debug
time: 15:02:54.817903+0000
process: Mail
subsystem: com.apple.network
category: connection
message: nw_protocol_socket_set_necp_attributes [C723.1.1:1] setsockopt 39 SO_NECP_ATTRIBUTES
…
you’ll at least know what the necp means (-:
Finally, a lot of NECP infrastructure is in the Darwin open source. As with all things in Darwin, it’s fine to poke around and see how your favourite feature works, but do not incorporate any information you find into your product. Stuff you uncover by looking in Darwin is not considered API.
[1] Settings > Cellular Data if you speak American (-:
[2] Network Extension providers can call the createTCPConnection(to:enableTLS:tlsParameters:delegate:) method to create an NWTCPConnection [3] that doesn’t run through the tunnel. You can use that if it’s convenient but you don’t need to use it.
[3] NWTCPConnection is now deprecated, but there are non-deprecated equivalents. For the full story, see NWEndpoint History and Advice.
Revision History
2025-12-12 Replaced “macOS networking stack” with “Apple networking stack” to avoid giving the impression that this is all about macOS. Added a link to NWEndpoint History and Advice. Made other minor editorial changes.
2023-02-27 First posted.
For important background information, read Extra-ordinary Networking before reading this.
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
On Host Names
I commonly see questions like How do I get the device’s host name? This question doesn’t make sense without more context. Apple systems have a variety of things that you might consider to be the host name:
The user-assigned device name — This is a user-visible value, for example, Guy Smiley. People set this in Settings > General > About > Name.
The local host name — This is a DNS name used by Bonjour, for example, guy-smiley.local. By default this is algorithmically derived from the user-assigned device name. On macOS, people can override this in Settings > General > Sharing > Local hostname.
The reverse DNS name associated with the various IP addresses assigned to the device’s various network interfaces
That last one is pretty much useless. You can’t get a single host name because there isn’t a single IP address. For more on that, see Don’t Try to Get the Device’s IP Address.
The other two have well-defined answers, although those answers vary by platform. I’ll talk more about that below.
Before getting to that, however, let’s look at the big picture.
Big Picture
The use cases for the user-assigned device name are pretty clear. I rarely see folks confused about that.
Another use case for this stuff is that you’ve started a server and you want to tell the user how to connect to it. I discuss this in detail in Showing Connection Information in an iOS Server.
However, most folks who run into problems like this do so because they’re suffering from one of the following misconceptions:
The device has a DNS name.
Its DNS name is unique.
Its DNS name doesn’t change.
Its DNS name is in some way useful for networking.
Some of these may be true in some specific circumstances, but none of them are true in all circumstances.
These issues are not unique to Apple platforms — if you look at the Posix spec for gethostname, it says nothing about DNS! — but folks tend to notice these problems more on Apple platforms because Apple devices are often deployed to highly dynamic network environments.
So, before you start using the APIs discussed in this post, think carefully about your assumptions.
And if you actually do want to work with DNS, there are two cases to consider:
If you’re looking for the local host name, use the APIs discussed above.
In other cases, it’s likely that the APIs in this post will not be helpful and you’d be better off focusing on DNS APIs [1].
[1] The API I recommend for this is DNS-SD. See the DNS section in TN3151 Choosing the right networking API.
macOS
To get the user-assigned device name, call the SCDynamicStoreCopyComputerName(_:_:) function. For example:
let userAssignedDeviceName = SCDynamicStoreCopyComputerName(nil, nil) as String?
To get the local host name, call the SCDynamicStoreCopyLocalHostName(_:) function. For example:
let localHostName = SCDynamicStoreCopyLocalHostName(nil) as String?
IMPORTANT This returns just the name label. To form a local host name, append .local..
Both routines return an optional result; code defensively!
If you’re displaying these values to the user, use the System Configuration framework dynamic store notification mechanism to keep your UI up to date.
iOS and Friends
On iOS, iPadOS, tvOS, and visionOS, get the user-assigned device name from the name property on UIDevice.
IMPORTANT Access to this is now restricted. For more on that, see the documentation for the com.apple.developer.device-information.user-assigned-device-name entitlement.
There is no direct mechanism to get the local host name.
Other APIs
There are a wide variety of other APIs that purport to return the host name. These include:
gethostname
The name property on NSHost [1]
The hostName property on NSProcessInfo (ProcessInfo in Swift)
These are problematic for a number of reasons:
They have a complex implementation that makes it hard to predict what value you’ll get back.
They might end up trying to infer the host name from the network environment.
The existing behaviour is hard to change due to compatibility concerns.
Some of them are marked as to-be-deprecated.
IMPORTANT The second issue is particularly problematic, because it involves synchronous DNS requests [2]. That’s slow in general. Worse yet, if the network environment is restricted in some way, these calls can be very slow, taking about 30 seconds to time out.
Given these problems, it’s generally best to avoid calling these routines at all.
[1] It also has a names property, which is a little closer to reality but still not particularly useful.
[2] Actually, that’s not true for gethostname. Rather, that call just returns whatever was last set by sethostname. This is always fast. The System Configuration framework infrastructure calls sethostname to update the host name as the system state changes.
Hi there,
How can I best understand the changes on the eSIM Installation wizard, i.e. on iOS 18 and later after an eSIM installation you used to get steps such as labeling the eSIM, deciding what to use for iMessage & FaceTime, what to use for mobile data, main voice line, etc.
Whereas on iOS 26 you are not prompted for these steps.
Hello team,
Would this mean that content filters intended for all browsing can only be implemented for managed devices using MDM? My goal would be to create a content filtering app for all users, regardless of if their device is managed/supervised.
thanks.
Topic:
App & System Services
SubTopic:
Networking
Just bought a macbook pro m4, im trying to run an api on port 5000, disabled airplay receiver, checked processes, ghost ones, hidden ones, and stuck ones. I didn't find a thing using the port, but i still get port in use.
Topic:
App & System Services
SubTopic:
Networking
I am developing a program on my chip and attempting to establish a connection with the WiFi Aware demo app launched by iOS 26. Currently, I am encountering an issue during the pairing phase.
If I am the subscriber of the service and successfully complete the follow-up frame exchange of pairing bootstrapping, I see the PIN code displayed by iOS.
Question 1: How should I use this PIN code?
Question 2: Subsequently, I need to negotiate keys with iOS through PASN. What should I use as the password for the PASN SAE process?
If I am the subscriber of the service and successfully complete the follow-up frame exchange of pairing bootstrapping, I should display the PIN code.
Question 3: How do I generate this PIN code?
Question 4: Subsequently, I need to negotiate keys with iOS through PASN. What should I use as the password for the PASN SAE process?
Topic:
App & System Services
SubTopic:
Networking
We’re looking to implement a custom IPSec IKEv2 VPN using the Packet Tunnel Provider network extension on iOS because we need to add extra information to EAP, which the built-in IKEv2 VPN configuration does not support.
Is it possible to handle the full IKEv2 negotiation and IPSec tunneling within the Packet Tunnel Provider extension? Or are there limitations that would prevent implementing a full IKEv2 stack this way?
Any insights or alternative approaches would be appreciated. Thanks!