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Widget Intent Configuration doesn't work in Swift 6
macOS: Sequoia Xcode: 16.1 I am working on a macOS app and it has a widget feature. When I use Swift 6 (Build Settings > Swift Language Version) in IntentExtension, the intent configuration won't show up in macOS Sequoia. If I downgrade to Swift 5, it works without any other changes. Is it a bug or am I missing something? How can I use Swift 6 with IntentExtension.
2
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758
Nov ’24
Snapshot error
Hey everyone, I have a problem with an app im creating. The code doesn't have any errors but the console has this that pops up: Snapshot request 0x1054191d0 complete with error: <NSError: 0x10541a970; domain: FBSSceneSnapshotErrorDomain; code: 4; "an unrelated condition or state was not satisfied"> { NSLocalizedDescription = an error occurred during a scene snapshotting operation; }
1
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86
Jun ’25
Using Dynamic Member Lookup in a Superclass
As a fun project, I'm wanting to model an electronic circuit. Components inherit from a superclass (ElectronicComponent). Each subclass (e.g. Resistor) has certain methods to return properties (e.g. resistance), but may vary by the number of outlets (leads) they have, and what they are named. Each outlet connects to a Junction. In my code to assemble a circuit, while I'm able to manually hook up the outlets to the junctions, I'd like to be able to use code similar to the following… class Lead: Hashable // implementation omitted { let id = UUID() unowned let component: ElectronicComponent weak var connection: Junction? init(component: ElectronicComponent, to connection: Junction? = nil) { self.component = component self.connection = connection } } @dynamicMemberLookup class ElectronicComponent { let id = UUID() var connections: Set<Lead> = [] let label: String? init(label: String) { self.label = label } subscript<T>(dynamicMember keyPath: KeyPath<ElectronicComponent, T>) -> T { self[keyPath: keyPath] } func connect(lead: KeyPath<ElectronicComponent, Lead>, to junction: Junction) { let lead = self[keyPath: lead] lead.connection = junction connections.insert(lead) } } class Resistor: ElectronicComponent { var input, output: Lead? let resistance: Measurement<UnitElectricResistance> init(_ label: String, resistance: Measurement<UnitElectricResistance>) { self.resistance = resistance super.init(label: label) } } let resistorA = Resistor("R1", resistance: .init(value: 100, unit: .ohms)) let junctionA = Junction(name: "A") resistorA.connect(lead: \.outlet2, to: junctionA) While I'm able to do this by implementing @dynamicMemberLookup in each subclass, I'd like to be able to do this in the superclass to save repeating the code. subscript<T>(dynamicMember keyPath: KeyPath<ElectronicComponent, T>) -> T { self[keyPath: keyPath] } Unfortunately, the compiler is not allowing me to do this as the superclass doesn't know about the subclass properties, and at the call site, the subclass isn't seen as ElectronicComponent. I've been doing trial and error with protocol conformance and other things, but hitting walls each time. One possibility is replacing the set of outlets with a dictionary, and using Strings instead of key paths, but would prefer not to. Another thing I haven't tried is creating and adopting a protocol with the method implemented in there. Another considered approach is using macros in the subclasses, but I'd like to see if there is a possibility of achieving the goal using my current approach, for learning as much as anything.
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351
Aug ’25
Returning One Component of Struct as Encoded Value in JSON
I have a class that I want to custom encode into JSON: class Declination: Decodable, Encodable { var asString: String var asDouble: Double init(_ asString: String) { self.asString = asString self.asDouble = raToDouble(asString) } required init(from decoder: Decoder) throws { let value = try decoder.singleValueContainer() self.asString = try value.decode(String.self) self.asDouble = declinationToDouble(asString) } } As you can see, I calculate the double form of the declination when I decode a JSON file containing the data. What I want to do now is ENCODE the class back out as a single string. Currently the standard JSON encode in Swift produces the following: "declination":{"asDouble":18.26388888888889,"asString":"+18:15:50.00"} what I want to produce is: declination:"+18:15:50.00" How can I easily do that? I've read up about custom encoders and such, and I get confused about the containers and what keys are being used. I think there might be a simple answer where I could just code: extension Coordinate: Encodable { func encode(to encoder: Encoder) throws { return encoder.encode(self.asString) } } But experienced Swift developers will immediately see that won't work. Should I do JSONSerialization instead? Can I just write a toString() extension and have JSON pick that up? Any help would be appreciated. Thanks, Robert
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320
Jan ’25
Swift optimization issue in macOS Sequoia
I'm using this library for encoding / decoding RSA keys. https://github.com/Kitura/BlueRSA It's worked fine up until macOS sequoia. The issue I'm having is the tests pass when in Debug mode, but the moment I switch to Release mode, the library no longer works. I ruled this down the swift optimization level. If I change the Release mode to no optimization, the library works again. Wondering where in the code this could be an issue? How would optimization break the functionality?
1
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542
Nov ’24
Passing string between Swift and C++
I want to understand what the recommended way is for string interoperability between swift and c++. Below are the 3 ways to achieve it. Approach 2 is not allowed at work due to restrictions with using std libraries. Approach 1: In C++: char arr[] = "C++ String"; void * cppstring = arr; std::cout<<"before:"<<(char*)cppstring<<std::endl;           // C++ String // calling swift function and passing the void buffer to it, so that swift can update the buffer content Module1::SwiftClass:: ReceiveString (cppstring, length);   std::cout<<"after:"<<(char*)cppstring<<std::endl;             // SwiftStr      In Swift: func ReceiveString (pBuffer : UnsafeMutableRawPointer , pSize : UInt ) -> Void { // to convert cpp-str to swift-str: let swiftStr = String (cString: pBuffer.assumingMemoryBound(to: Int8.self)); print("pBuffer content: \(bufferAsString)"); // to modify cpp-str without converting: let swiftstr:String = "SwiftStr"      _ =  swiftstr.withCString { (cString: UnsafePointer<Int8>) in pBuffer.initializeMemory(as: Int8.self, from: cString, count: swiftstr.count+1) } }  Approach 2:  The ‘String’ type returned from a swift function is received as ‘swift::String’ type in cpp. This is implicitly casted to std::string type. The std::string has the method available to convert it to char *. void TWCppClass::StringConversion () {     // GetSwiftString() is a swift call that returns swift::String which can be received in std::string type     std::string stdstr = Module1::SwiftClass::GetSwiftString ();     char * cstr = stdstr.data ();     const char * conststr= stdstr.c_str (); }    Approach 3: The swift::String type that is obtained from a swift function can be received in char * by directly casting the address of the swift::String. We cannot directly receive a swift::String into a char *. void TWCppClass::StringConversion () {    // GetSwiftString() is a swift call that returns swift::String    swift::String swiftstr = Module1::SwiftClass::GetSwiftString ();    // obtaining the address of swift string and casting it into char *    char * cstr = (char*)&swiftstr; }
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385
Jul ’25
Best way to measure days between dates
Hey team I'm facing an issue where startDate is 1 January 2025 and endDate is 31 March 2025 between this 2 dates is 90 days, but on my code is being taken as 89 days I've seen the math of the code excludes the first partial day (from midnight to 06:00) on 2025-01-01, which results in 89 full days instead of 90 days. startDate: 2025-01-01 06:00:00 +0000 endDate: 2025-03-31 06:00:00 +0000 this is my function func daysBetweenDates() -> Int? { guard let selectedStartDate = selectedStartDate?.date else { return nil } guard let selectedEndDate = selectedEndDate?.date else { return 0 } let calendar = Calendar.current let dateComponents = calendar.dateComponents([.day], from: selectedStartDate, to: selectedEndDate) return dateComponents.day } what I've tried is reset the hours to 0 so it can take the full day and return 90 days like this func daysBetweenDates() -> Int? { guard let selectedStartDate = selectedStartDate?.date else { return nil } guard let selectedEndDate = selectedEndDate?.date else { return 0 } var calendar = Calendar(identifier: .gregorian) calendar.timeZone = TimeZone(secondsFromGMT: 0) ?? .current let cleanMidNightStartDate = calendar.startOfDay(for: selectedStartDate) let cleanMidNightEndDate = calendar.startOfDay(for: selectedEndDate.addingTimeInterval(24 * 60 * 60)) let dateComponents = calendar.dateComponents([.day], from: cleanMidNightStartDate, to: cleanMidNightEndDate) let daysCount = dateComponents.day ?? 0 return daysCount } this worked for that date specifically but when I tried to change the date for example startDate: 18 December 2024. endDate: 18 March 2025. between those dates we have 90 days but this function now reads 91. what I'm looking is a cleaver solution for this problem so I can have the best posible quality code, thanks in advance!
1
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475
Dec ’24
Circular Reference Error in Xcode 26
I have my project running perfectly fine on Xcode 16. However, in Xcode 26 it doesn't build due to an error that I do not understand. I have three files that pertain to this error: // FriendListResponse.swift import Foundation struct FriendListResponse: Decodable { var friendships: [Friendship] var collections: [FriendCollection] } // Friendship.swift import Foundation struct Friendship: Decodable { var createdAt: String var friendId: Int var friendUserId: Int // user ID of the friend var friendUsername: String var id: Int var tagNames: [String] } // FriendCollection.swift struct FriendCollection: Decodable { var id: Int var permalink: String var tagNames: [String] var title: String } On the first file, FriendListResponse.swift, I am the simple error message "circular reference." I do not understand how these self-contained structs could create a circular reference. Although I have other data types in my project, none of them are even referenced in these files except for Friendship and FriendCollection. The FriendListResponse is a struct that is created from JSON values that are fetched from an API. This is the function that fetches the JSON: public static func listFriends(username: String) async throws -> [Friendship] { let data = try await sendGETRequest( url: "people/\(username)/friends/list.json" ) print(String(data: data, encoding: .utf8)!) let decoder = JSONDecoder() decoder.keyDecodingStrategy = .convertFromSnakeCase let wrapper = try decoder.decode(FriendListResponse.self, from: data) return wrapper.friendships } // Note: the function sendGETRequest is just // a function that I have created that takes a set // of parameters and returns a data object // using the HTTP GET protocol. I don't think // that it is related to this issue. However, if you // think that it is, I can share the code for that. This error has also happened in a few other cases within contained networks of my data structure. I do not know why this error is only appearing once I launch Xcode 26 beta with my project files. I would think that this error also would appear in Xcode 16.4. Any help would be greatly appreciated in my process to compile my project on Xcode 26!
7
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303
Jun ’25
NSDictionary.isEqual(to:) with Swift dictionary compiles on macOS but not on iOS
The following code works when compiling for macOS: print(NSMutableDictionary().isEqual(to: NSMutableDictionary())) but produces a compiler error when compiling for iOS: 'NSMutableDictionary' is not convertible to '[AnyHashable : Any]' NSDictionary.isEqual(to:) has the same signature on macOS and iOS. Why does this happen? Can I use NSDictionary.isEqual(_:) instead?
2
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471
Feb ’25
Actor and the Singleton Pattern
As I migrate my apps to Swift 6 one by one, I am gaining a deeper understanding of concurrency. In the process, I am quite satisfied to see the performance benefits of parallel programming being integrated into my apps. At the same time, I have come to think that actor is a great type for addressing the 'data race' issues that can arise when using the 'singleton' pattern with class. Specifically, by using actor, you no longer need to write code like private let lock = DispatchQueue(label: "com.singleton.lock") to prevent data races that you would normally have to deal with when creating a singleton with a class. It reduces the risk of developer mistakes. import EventKit actor EKDataStore: Sendable { static let shared = EKDataStore() let eventStore: EKEventStore private init() { self.eventStore = EKEventStore() } } Of course, since a singleton is an object used globally, it can become harder to manage dependencies over time. There's also the downside of not being able to inject dependencies, which makes testing more difficult. I still think the singleton pattern is ideal for objects that need to be maintained throughout the entire lifecycle of the app with only one instance. The EKDataStore example I gave is such an object. I’d love to hear other iOS developers' opinions, and I would appreciate any advice on whether I might be missing something 🙏
1
0
1.5k
Sep ’24
Hash Collision in Data type
I notice that Swift Data type's hashValue collision when first 80 byte of data and data length are same because of the Implementation only use first 80 bytes to compute the hash. https://web.archive.org/web/20120605052030/https://opensource.apple.com/source/CF/CF-635.21/CFData.c also, even if hash collision on the situation like this, I can check data is really equal or not by == does there any reason for this implementation(only use 80 byte of data to make hashValue)? test code is under below let dataArray: [UInt8] = [ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ] var dataArray1: [UInt8] = dataArray var dataArray2: [UInt8] = dataArray dataArray1.append(contentsOf: [0x00, 0x00, 0x00, 0x00]) dataArray2.append(contentsOf: [0xff, 0xff, 0xff, 0xff]) let data1 = Data(dataArray1) let data2 = Data(dataArray2) // Only last 4 byte differs print(data1.hashValue) print(data2.hashValue) print(data1.hashValue == data2.hashValue) // true print(data1 == data2) // false
1
0
553
Feb ’25
How to dismiss an ImmersiveSpace when the main window closes?
I noticed that when I enter the fully immersive view and then click the X button below the window, the immersive space remains active, and the only way to dismiss it is to click the digital crown. On other apps (Disney+ for example), closing out of the main window while in immersive mode also closes out the immersive space. I tried applying an onDisappear modifier to the the Modules view with a dismissImmersiveSpace, but that doesn't appear to do anything. Any help would be appreciated.
1
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450
Dec ’24
Crash in libswiftCore with swift::RefCounts
I'm seeing somewhat regular crash reports from my app which appear to be deep in the Swift libraries. They're happening in the same spot, so I'm apt to believe something is likely getting deallocated behind the scenes - but I don't really know how to guard against it. Here's the specific crash thread: 0 libsystem_kernel.dylib 0x00000001d51261dc __pthread_kill + 8 (:-1) 1 libsystem_pthread.dylib 0x000000020eaa8b40 pthread_kill + 268 (pthread.c:1721) 2 libsystem_c.dylib 0x000000018c5592d0 abort + 124 (abort.c:122) 3 libsystem_malloc.dylib 0x0000000194d14cfc malloc_vreport + 892 (malloc_printf.c:251) 4 libsystem_malloc.dylib 0x0000000194d14974 malloc_report + 64 (malloc_printf.c:290) 5 libsystem_malloc.dylib 0x0000000194d0e8b4 ___BUG_IN_CLIENT_OF_LIBMALLOC_POINTER_BEING_FREED_WAS_NOT_ALLOCATED + 32 (malloc_common.c:227) 6 Foundation 0x0000000183229f40 __DataStorage.__deallocating_deinit + 104 (Data.swift:563) 7 libswiftCore.dylib 0x0000000182f556c8 _swift_release_dealloc + 56 (HeapObject.cpp:847) 8 libswiftCore.dylib 0x0000000182f5663c bool swift::RefCounts&lt;swift::RefCountBitsT&lt;(swift::RefCountInlinedness)1&gt;&gt;::doDecrementSlow&lt;(swift::PerformDeinit)1&gt;(swift::RefCountBitsT&lt;(swift::RefCountInlinedness)1&gt;, unsigned int) + 152 (RefCount.h:1052) 9 TAKAware 0x000000010240c688 StreamParser.parseXml(dataStream:) + 1028 (StreamParser.swift:0) 10 TAKAware 0x000000010240cdb4 StreamParser.processXml(dataStream:forceArchive:) + 16 (StreamParser.swift:85) 11 TAKAware 0x000000010240cdb4 StreamParser.parseCoTStream(dataStream:forceArchive:) + 360 (StreamParser.swift:108) 12 TAKAware 0x000000010230ac3c closure #1 in UDPMessage.connect() + 252 (UDPMessage.swift:68) 13 Network 0x000000018506b68c closure #1 in NWConnectionGroup.setReceiveHandler(maximumMessageSize:rejectOversizedMessages:handler:) + 200 (NWConnectionGroup.swift:458) 14 Network 0x000000018506b720 thunk for @escaping @callee_guaranteed (@guaranteed OS_dispatch_data?, @guaranteed OS_nw_content_context, @unowned Bool) -&gt; () + 92 (&lt;compiler-generated&gt;:0) 15 Network 0x0000000185185df8 invocation function for block in nw_connection_group_handle_incoming_packet(NWConcrete_nw_connection_group*, NSObject&lt;OS_nw_endpoint&gt;*, NSObject&lt;OS_nw_endpoint&gt;*, NSObject&lt;OS_nw_interface&gt;*, NSObje... + 112 (connection_group.cpp:1075) 16 libdispatch.dylib 0x000000018c4ad2b8 _dispatch_block_async_invoke2 + 148 (queue.c:574) 17 libdispatch.dylib 0x000000018c4b7584 _dispatch_client_callout + 16 (client_callout.mm:85) 18 libdispatch.dylib 0x000000018c4d325c _dispatch_queue_override_invoke.cold.3 + 32 (queue.c:5106) 19 libdispatch.dylib 0x000000018c4a21f8 _dispatch_queue_override_invoke + 848 (queue.c:5106) 20 libdispatch.dylib 0x000000018c4afdb0 _dispatch_root_queue_drain + 364 (queue.c:7342) 21 libdispatch.dylib 0x000000018c4b054c _dispatch_worker_thread2 + 156 (queue.c:7410) 22 libsystem_pthread.dylib 0x000000020eaa5624 _pthread_wqthread + 232 (pthread.c:2709) 23 libsystem_pthread.dylib 0x000000020eaa29f8 start_wqthread + 8 (:-1) Basically we're receiving a message via UDP that is an XML packet. We're parsing that packet using what I think it pretty straightforward code that looks like this: func parseXml(dataStream: Data?) -&gt; Array&lt;String&gt; { var events: [String] = [] guard let data = dataStream else { return events } currentDataStream.append(data) var str = String(decoding: currentDataStream, as: UTF8.self) while str.contains(StreamParser.STREAM_DELIMTER) { let splitEvent = str.split(separator: StreamParser.STREAM_DELIMTER, maxSplits: 1) let cotEvent = splitEvent.first! var restOfString = "" if splitEvent.count &gt; 1 { restOfString = String(splitEvent.last!) } events.append("\(cotEvent)\(StreamParser.STREAM_DELIMTER)") str = restOfString } currentDataStream = Data(str.utf8) return events } the intention is that the message may be broken across multiple packets, so we build them up here. Is there anything I can do to guard against these crashes?
5
0
178
Jul ’25
String functions problems on iOS18
On iOS 18 some string functions return incorrect values in some cases. Found problems on replacingOccurrences() and split() functions, but there may be others. In the results of these functions in some cases a character is left in the result string when it shouldn't. This did not happen on iOS17 and older versions. I created a very simple Test Project to reproduce the problem. If I run these tests on iOS17 or older the tests succeed. If I run these tests on iOS18 the tests fail. test_TestStr1() function shows a problem in replacingOccurrences() directly using strings. test_TestStr2() function shows a problem in split() that seems to happen only when bridging from NSString to String. import XCTest final class TestStrings18Tests: XCTestCase { override func setUpWithError() throws { // Put setup code here. This method is called before the invocation of each test method in the class. } override func tearDownWithError() throws { // Put teardown code here. This method is called after the invocation of each test method in the class. } func test_TestStr1() { let str1 = "_%\u{7}1\u{7}_"; let str2 = "%\u{7}1\u{7}"; let str3 = "X"; let str4 = str1.replacingOccurrences(of: str2, with: str3); //This should be true XCTAssertTrue(str4 == "_X_"); } func test_TestStr2() { let s1 = "TVAR(6)\u{11}201\"Ã\"\u{11}201\"A\""; let s2 = s1.components(separatedBy: "\u{11}201"); let t1 = NSString("TVAR(6)\u{11}201\"Ã\"\u{11}201\"A\"") as String; let t2 = t1.components(separatedBy: "\u{11}201"); XCTAssertTrue(s2.count == t2.count); let c = s2.count //This should be True XCTAssertTrue(s2[0] == t2[0]); } }
6
0
493
Feb ’25
ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS
Is this possible while inserting a String into Set Crashed: com.apple.root.user-initiated-qos.cooperative 0 libswiftCore.dylib 0xf4c0 _assertionFailure(_:_:flags:) + 136 1 libswiftCore.dylib 0x17f484 ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS(_:) + 3792 2 MyEatApp 0x44f6e8 specialized _NativeSet.insertNew(_:at:isUnique:) + 4333926120 (&lt;compiler-generated&gt;:4333926120) 3 MyEatApp 0x44eaec specialized Set._Variant.insert(_:) + 4333923052 (&lt;compiler-generated&gt;:4333923052) 4 MyEatApp 0x479f7c HomeViewModel.hanldeAnnouncementCard(from:) + 293 (HomeViewModel+PersonalizedOffer.swift:293) 5 libswift_Concurrency.dylib 0x5c134 swift::runJobInEstablishedExecutorContext(swift::Job*) + 292 6 libswift_Concurrency.dylib 0x5d5c8 swift_job_runImpl(swift::Job*, swift::SerialExecutorRef) + 156 7 libdispatch.dylib 0x13db0 _dispatch_root_queue_drain + 364 8 libdispatch.dylib 0x1454c _dispatch_worker_thread2 + 156 9 libsystem_pthread.dylib 0x9d0 _pthread_wqthread + 232 10 libsystem_pthread.dylib 0xaac start_wqthread + 8
6
0
307
Aug ’25
Dateformatter returns date in incorrect format
I have configured DateFormatter in the following way: let df = DateFormatter() df.dateFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'" df.locale = .init(identifier: "en") df.timeZone = .init(secondsFromGMT: 0) in some user devices instead of ISO8601 style it returns date like 09/25/2024 12:00:34 Tried to change date format from settings, changed calendar and I think that checked everything that can cause the problem, but nothing helped to reproduce this issue, but actually this issue exists and consumers complain about not working date picker. Is there any information what can cause such problem? May be there is some bug in iOS itself?
1
0
415
Feb ’25
Label cannot export localized string key
Hello all. This is my code snippet. RecordListView() .tabItem { Label("Record List", systemImage: "list.clipboard") } .tag(Tab.RecordList) When I export localizations, there is no Record List in the .xcloc file. Then I use LocalizedStringKey for Label and export localizations file, the code is as follows: let RecordsString:LocalizedStringKey = "Tab.Records" RecordListView() .tabItem { Label(RecordsString, systemImage: "list.clipboard") } .tag(Tab.RecordList) There is still no Tab.Records.
2
0
605
Nov ’24
Interpreting received "Data" object in cpp
Hello Everyone, I have a use case where I wanted to interpret the "Data" object received as a part of my NWConnection's recv call. I have my interpretation logic in cpp so in swift I extract the pointer to the raw bytes from Data and pass it to cpp as a UnsafeMutableRawPointer. In cpp it is received as a void * where I typecast it to char * to read data byte by byte before framing a response. I am able to get the pointer of the bytes by using // Swift Code // pContent is the received Data if let content = pContent, !content.isEmpty { bytes = content.withUnsafeBytes { rawBufferPointer in guard let buffer = rawBufferPointer.baseAddress else { // return with null data. } // invoke cpp method to interpret data and trigger response. } // Cpp Code void InterpretResponse (void * pDataPointer, int pDataLength) { char * data = (char *) pDataPointer; for (int iterator = 0; iterator < pDataLength; ++iterator ) { std::cout << data<< std::endl; data++; } } When I pass this buffer to cpp, I am unable to interpret it properly. Can someone help me out here? Thanks :) Harshal
4
0
947
Dec ’24