1.js

conn = xpc_connection_create_mach_service(
    "com.apple.coreservices.launchservicesd",
    _dispatch_root_queues + 256,
    XPC_CONNECTION_MACH_SERVICE_PRIVILEGED);

Conversation on XPC connection:

setupServerConnection
{
"session": 186a4,
"clientversion": u10900000,
"command": 64
}
{
"session": 186a4,
"serverversion": u10900000,
"success": true
}

----------------------

_LSApplicationCheckIn
{
  "deathport": <unknown>,
  "info": {
    "LSCheckInTime*": <date:138fde193afe2700>,
    "LSDisplayName": "node",
    "LSArchitecture": "x86_64",
    "CFBundleExecutablePath": "/Users/indutny/Code/indutny/tls.js/../node/out/Debug/node"
  },
  "command": 1f4,
  "apptaskport": <unknown>
}
{
  "result": {
    "LSParentASN": {
      "com.apple.coreservices.asn.lo": u5c05c,
      "com.apple.coreservices.asn.hi": u0,
      "com.apple.coreservices.asn": <uuid>
    },
    "LSApplicationHasRegistered": true,
    "LSParentASNWasInferred": true,
    "pid": a6b,
    "LSCheckInTime*": <date:138fde193afe2700>,
    "ApplicationType": "BackgroundOnly",
    "LSDisplayName": "node",
    "ChangeCount": 201,
    "LSExecutableFilenameLowerCaseKey": "node",
    "CanBecomeFrontmost": false,
    "LSASN": {
      "com.apple.coreservices.asn.lo": u386386,
      "com.apple.coreservices.asn.hi": u0,
      "com.apple.coreservices.asn": <uuid>
    },
    "CFBundleExecutablePath": "/Users/indutny/Code/indutny/tls.js/../node/out/Debug/node",
    "LSArchitecture": "x86_64"
  },
  "success": true
}

-----------------

setupServerConnection
{
  "session": 186a4,
  "clientversion": u10900000,
  "command": 64
}
{
  "session": 186a4,
  "serverversion": u10900000,
  "success": true
}

-------------------

_LSSetApplicationInformation
{
  "returncurrent": true,
  "info": {
    "CFBundleExecutablePathDeviceID": 1000002,
    "CFBundleExecutablePathINode": 16ebcd5
  },
  "command": 1fe,
  "asn": u386386
}
{
  "info": {
    "LSParentASN": {
      "com.apple.coreservices.asn.lo": u5c05c,
      "com.apple.coreservices.asn.hi": u0,
      "com.apple.coreservices.asn": <uuid>
    },
    "pid": a6b,
    "LSParentASNWasInferred": true,
    "LSCheckInTime*": <date:138fde193afe2700>,
    "LSDisplayName": "node",
    "ChangeCount": 200,
    "LSExecutableFilenameLowerCaseKey": "node",
    "LSASN": {
      "com.apple.coreservices.asn.lo": u386386,
      "com.apple.coreservices.asn.hi": u0,
      "com.apple.coreservices.asn": <uuid>
    },
    "LSArchitecture": "x86_64",
    "CFBundleExecutablePath": "/Users/indutny/Code/indutny/tls.js/../node/out/Debug/node"
  },
  "success": true
}

-----------------------

_LSSetApplicationInformation
{
  "info": {
    "LSDisplayName": "hello"
  },
  "command": 1fe,
  "asn": u100000a6b
}
{
  "info": {
    "LSParentASN": {
      "com.apple.coreservices.asn.lo": u5c05c,
      "com.apple.coreservices.asn.hi": u0,
      "com.apple.coreservices.asn": <uuid>
    },
    "LSApplicationHasRegistered": true,
    "LSParentASNWasInferred": true,
    "pid": a6b,
    "LSCheckInTime*": <date:138fde193afe2700>,
    "ApplicationType": "BackgroundOnly",
    "LSDisplayName": "hello",
    "ChangeCount": 204,
    "CFBundleExecutablePathDeviceID": 1000002,
    "LSExecutableFilenameLowerCaseKey": "node",
    "CFBundleExecutablePathINode": 16ebcd5,
    "CanBecomeFrontmost": false,
    "LSASN": {
      "com.apple.coreservices.asn.lo": u386386,
      "com.apple.coreservices.asn.hi": u0,
      "com.apple.coreservices.asn": <uuid>
    },
    "CFBundleExecutablePath": "/Users/indutny/Code/indutny/tls.js/../node/out/Debug/node",
    "LSArchitecture": "x86_64"
  },
  "success": true
}