signpost_bits

gistfile1.txt

Hi!  Thanks for looking

TL;DR - trying to do anything with os_signpost, but nothing is appearing in instruments.
UPDATE: on devices it's working.  Is it supposed to work in the simulator?  Points of Interest are on built-in templates, I figured it should work on the device...

The app is all objc, using the C API.  See at the end for a swift attempt

More details:

Creating the log like this:

+ (os_log_t) pointsOfInterestLog {
    static dispatch_once_t predicate;
    static os_log_t log;

    dispatch_once(&predicate, ^{
        log = os_log_create("com.bundle.id.signpoints",
                            OS_LOG_CATEGORY_POINTS_OF_INTEREST);
    });

    if (!os_log_info_enabled(log)) {
        exit(55);
    }
    return log;

} // pointsOfInterestLog


calling like

    os_signpost_event_emit(MJSignpost.pointsOfInterestLog, OS_SIGNPOST_ID_EXCLUSIVE, "Layout2");

(also tried it with a generated os_signpost_id_generate)

Tried calling it between a 

    os_signpost_interval_begin(MJSignpost.log, OS_SIGNPOST_ID_EXCLUSIVE, "Layout");
    os_signpost_interval_end(MJSignpost.log, OS_SIGNPOST_ID_EXCLUSIVE, "Layout");

pairing, using a log created with   os_log_create("com.bundle.id.signpoints", "App Name");
(those don't appear in instruments either when using the os_signpost instruments added to the time profiler template)

Looked at the preprocessed output, and the `(_os_signpost_emit_with_name_impl)` call is being reached, 
so any prior gates aren't being triggered.

When I record in instruments (default time profiler template) and cause this thing to be hit fairly often (say several times a 
second during user interaction), I get "no data, call os_signpost on a logging handle with the
PointsOfInterest category"

No additional command-line arguments or environment variables.


-------

private let refreshLog = OSLog(subsystem: "com.bundle.id.signpots",
                               category: .pointsOfInterest)
(declared outside of any class - up in file scope)
                               
        os_signpost(.event, log: refreshLog, name: "Fetch-pre")
        os_signpost(.begin, log: refreshLog, name: "Fetch")
        os_signpost(.event, log: refreshLog, name: "Fetch-inside")

os_signpost(.end, log: refreshLog, name: "Fetch")

Nothing showing up in points of interest.  And when using a non-pointsOfInterest category.


-----

Here's is a complete implementation that tries to make a point of interest on each button tap:

import UIKit
import os.signpost

private let refreshLog = OSLog(subsystem: "com.blorgle.signpots",
                               category: .pointsOfInterest)

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    @IBAction func blah() {
        os_signpost(.event, log: refreshLog, name: "Fetchpre")
    }

}

and no joy.