Services are an abstraction of ports and are the commonly used way of inter-process communication outside of the kernel. While handles of regular ports are retrieved from svcConnectToPort, service handles are retrieved through the port srv: ("service manager").

When a service is registered, svcCreatePort is used without a port-name. This means that the port is inaccessible via the port SVCs outside of sm-module. See below for getting a session handle for sending commands to services.

Processes with PID less than or equal to the number of NATIVE_FIRM built-in modules (fs, sm, pm, pxi, ldr) have access to all services. This value is obtained from svcGetSystemInfo.

Attempting to use GetServiceSession with a service that the process has access to when that service isn't registered, results in svcSendSyncRequest never returning(the exact cause is unknown).

Service Manager Port "srv:"

Command Header Description
0x00010002 RegisterClient
0x00020000 EnableNotification
0x00030100 RegisterService
0x000400C0 UnregisterService
0x00050100 GetServiceHandle
0x000600C2 RegisterPort
0x000700C0 UnregisterPort
0x00080100 GetPort
0x00090040 Subscribe
0x000A0040 Unsubscribe
0x000B0000 ReceiveNotification
0x000C0080 PublishToSubscriber
0x000D0040 PublishAndGetSubscriber
0x000E00C0 IsServiceRegistered

Service Manager Process-Manager Port/Service "srv:pm"

Command Header (port), prior to 7.0.0-13 Command Header (service), post 7.0.0-13 Description
0x04010042 0x00010042 PublishToProcess
0x04020040 0x00020040 PublishToAll
0x04030082 0x00030082 RegisterProcess
0x04040040 0x00040040 UnregisterProcess

Prior to to 7.0.0-13, the commands listed for "srv:" were also accessible under this port with the same command-headers. Starting with 7.0.0-13, the "srv:pm" port was changed to a service. With this change, commandIDs for these commands were changed. "srv:pm" was originally vulnerable, this was fixed with 7.0.0-13, see here. Originally any process could use "srv:pm", however starting with 7.0.0-13 only the built-in NATIVE_FIRM sysmodules have access to it. The only system title which uses "srv:pm" is the Process Manager.

Notifications

ID Description
0x100 This indicates that all processes must terminate: power-off, reboot, or FIRM-launch.
0x104 This indicates that the system is entering sleep mode. (PTM:NotifySleepPreparationComplete needed for this and the following?)
0x105 This indicates that the system has exited sleep mode.
0x107 Unknown. Subscribed to by CECD module.
0x108 error at boot?
0x109 ? (Subscribed to by GSP)
0x10C Unknown.
0x110-0x11F Unknown. See PM launch flags.
0x179 Unknown.
0x202 POWER button pressed
0x203 POWER button held long
0x204 HOME button pressed
0x205 HOME button released
0x206 This is signaled by NWMEXT:ControlWirelessEnabled and when the physical Wi-Fi slider is enabled
0x207 SD card inserted
0x208 Game cartridge inserted
0x209 SD card removed
0x20A Game cartridge removed
0x20B Game cartridge inserted or removed
0x20D ? (Subscribed to by GSP)
0x20E ? (Subscribed to by GSP)
0x213 ? (Subscribed to by GSP)
0x214 ? (Subscribed to by GSP)
0x302 Unknown. Signaled by nwm module.
0x303 Unknown. Subscribed to by CECD module.
0x304 Unknown. Subscribed to by CECD module.