Perform some of Dock actions programmatically.

dock_actions.m

#import <dlfcn.h>

void sendMessageToDock(NSString *message) {
    static dispatch_once_t onceToken;
    static void (*ptrCoreDockSendNotification)(CFStringRef, int) = NULL;
    dispatch_once(&onceToken, ^{
        void *handle = dlopen("/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/HIServices.framework/Versions/A/HIServices", RTLD_LAZY);
        if (!handle) {
            return;
        }
        ptrCoreDockSendNotification = dlsym(handle, "CoreDockSendNotification");
    });
    if (ptrCoreDockSendNotification) {
        ptrCoreDockSendNotification((CFStringRef) message, 0);
    }
}

int main(int argc, const char * argv[]) {
    /*
     Possible messages:
      - "com.apple.launchpad.toggle": Toggle Launchpad
      - "com.apple.expose.awake": Toggle Mission Control
      - "com.apple.expose.front.awake": Toggle App Exposé
      - "com.apple.showdesktop.awake": Toggle desktop
     */
    sendMessageToDock(@"com.apple.launchpad.toggle");
    return 0;
}