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Cydia Package
Developer Alan Yip
Package ID libobjcipc
Latest Version 1.0.0

libobjcipc is a developer library that provides an inter-process communication (between app and SpringBoard) solution for jailbroken iOS. It handles the socket connections between SpringBoard and app processes, the automatic set up of process assertions and the auto disconnection after timeout or the process terminates.

You only need to call the static methods in the main class OBJCIPC. Messages and replies can be sent synchronously (blocking) or asynchronously.

Header and source code are available on [1]. You may find the library file at /usr/lib/libobjcipc.dylib on a device.

Basic Usage

The basic usage of the library is to have an extra MobileSubstrate extension which hooks into a specific app to set up an incoming message handler. Another instance in SpringBoard process sends a message to that app and wait for its reply, and vice versa. Messages can be sent from either end.

The library ensures that the receiver is able to receive new messages so it will make the app process stay in background until timeout occurs. Some potential problems, for instance the app is not opened yet or crashes, are appropriately handled by the library itself. In such cases, the messages are sent once the app process is opened or the sender gets an instant empty reply if there is any problem in the receiver (e.g. the app crashes).

If you encounter any crashes in the receiver end, check whether the incoming message handler (block) in the receiver end causes any crashes.

Send message

// Asynchronous message sent from SpringBoard to app (MobileTimer in this case)
[OBJCIPC sendMessageToAppWithIdentifier:@"" messageName:@"Custom.Message.Name" dictionary:@{ @"key": @"value" } replyHandler:^(NSDictionary *response) {
    NSLog(@"Received reply from MobileTimer: %@", response);

// Asynchronous message sent from app to SpringBoard
[OBJCIPC sendMessageToSpringBoardWithMessageName:@"Custom.Message.Name" dictionary:@{ @"key": @"value" } replyHandler:^(NSDictionary *response) {
    NSLog(@"Received reply from SpringBoard: %@", response);

// Omit replyHandler parameter to send messages synchronously; return value will be the reply (NSDictionary).

Handle incoming messages

// Handle messages sent from any app in SpringBoard
[OBJCIPC registerIncomingMessageFromAppHandlerForMessageName:@"Custom.Message.Name"  handler:^NSDictionary *(NSDictionary *message) {
    // return something as reply
    return nil;

// Handle messages sent from the specific app in SpringBoard
[OBJCIPC registerIncomingMessageHandlerForAppWithIdentifier:@"" andMessageName:@"Custom.Message.Name" handler:^NSDictionary *(NSDictionary *message) {
    // return something as reply
    return nil;

// Handle messages sent from SpringBoard in app
[OBJCIPC registerIncomingMessageFromSpringBoardHandlerForMessageName:@"Custom.Message.Name" handler:^NSDictionary *(NSDictionary *message) {
    // return something as reply
    return nil;

Example Projects

Project Author
Subproject in Google Authenticator for ProWidgets Alan Yip