How to get information about free memory and running processes in an App Store approved app? (Yes, there is one!)

There is an app called "Activity Monitor Touch" in the App Store, which displays background processes as well as free memory.

So there MUST be an public API to access this information. The evidence:

I'm already searching for days but can't find any good starting point. How can this app figure all this stuff out without any jailbreaking / hacking / etc.?

Until recently I was sure that something like this is absolutely impossible on iOS.

I've found this code snippet:

- (NSArray *)runningProcesses {

    int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_ALL, 0};
    size_t miblen = 4;

    size_t size;
    int st = sysctl(mib, miblen, NULL, &size, NULL, 0);

    struct kinfo_proc * process = NULL;
    struct kinfo_proc * newprocess = NULL;

    do {

        size += size / 10;
        newprocess = realloc(process, size);

        if (!newprocess){

            if (process){
                free(process);
            }

            return nil;
        }

        process = newprocess;
        st = sysctl(mib, miblen, process, &size, NULL, 0);

    } while (st == -1 && errno == ENOMEM);

    if (st == 0){

        if (size % sizeof(struct kinfo_proc) == 0){
            int nprocess = size / sizeof(struct kinfo_proc);

            if (nprocess){

                NSMutableArray * array = [[NSMutableArray alloc] init];

                for (int i = nprocess - 1; i >= 0; i--){

                    NSString * processID = [[NSString alloc] initWithFormat:@"%d", process[i].kp_proc.p_pid];
                    NSString * processName = [[NSString alloc] initWithFormat:@"%s", process[i].kp_proc.p_comm];

                    NSDictionary * dict = [[NSDictionary alloc] initWithObjects:[NSArray arrayWithObjects:processID, processName, nil] 
                                                                        forKeys:[NSArray arrayWithObjects:@"ProcessID", @"ProcessName", nil]];
                    [processID release];
                    [processName release];
                    [array addObject:dict];
                    [dict release];
                }

                free(process);
                return [array autorelease];
            }
        }
    }

    return nil;
}

But I can't make it run on the iPhone. Xcode doesn't know these symbols: CTL_KERN, KERN_PROC, KERN_PROC_ALL

So of course I must import a header file or library. Does anyone know where these belong to, and how the headers must be imported to make this work?

Solution 1:

Works like a charm:

#import <sys/sysctl.h>

Solution 2:

sysctl is no longer accessible to sandboxed iOS 9 apps.

From WWDC 2015 session 703 Privacy and Your App:

In iOS 9, the sandbox now prevents a process from accessing the kern.proc, kern.procargs, and kern.procargs2 values for other processes

and

iOS apps are not permitted to see what other apps are running

So even if you find a way, you are likely to get rejected from the App Store.

https://developer.apple.com/videos/play/wwdc2015-703/