GSCapability
GSCapability is a group of C functions that checks the capability of the device. A capability can be anything from a simple boolean value (such as whether the device can take pictures) to a complex structure (such as the screen dimensions).
- Note: On iOS 7, GSSystemHasCapability (see example below) crashes with _abort unless you query for @'explicitContentRestriction". You should use MGGetBoolAnswer instead.
See also: GSC bit on TheiPhoneWiki.
Contents
Example code
if (GSSystemHasCapability(kGSMagnetometerCapability)) {
direction = get_direction();
} else {
printf("This device has no compass\n");
}
Extracting the capability dictionary
The capabilities are stored as a plist in a shared memory region named "GSCapabilities". You can use this code to extract it:
#include <sys/mman.h>
#include <sys/stat.h>
#include <CoreFoundation/CoreFoundation.h>
static CFDictionaryRef GSCopyCapabilities(void) {
int shm = shm_open("GSCapabilities", 0);
assert(shm != -1);
struct stat shm_stat;
int fstat_ret = fstat(shm, &shm_stat);
assert(fstat_ret == 0);
void* map = mmap(NULL, shm_stat.st_size, 1, 1, shm, 0);
assert(map >= 0);
CFIndex len = *(CFIndex*)map;
CFDataRef data = CFDataCreateWithBytesNoCopy(NULL, (const UInt8*)map + sizeof(len), len, kCFAllocatorNull);
assert(data != NULL);
CFPropertyListRef propList = CFPropertyListCreateFromXMLData(NULL, data, kCFPropertyListImmutable, NULL);
CFRelease(data);
munmap(map, len);
close(shm);
return propList;
}
This shared memory is constructed by the SBPlatformController class in SpringBoard.
Default capabilities of various devices
| Capabilities | N45AP (iPod Touch 1G) |
M68AP (iPhone 2G) |
N88AP (iPhone 3GS) |
K48AP (iPad) |
N90AP (iPhone 4) |
|---|---|---|---|---|---|
| kGSTelephonyCapability "telephony" |
No | Yes | Yes | No | Yes |
| kGSCellularDataCapability "cellular-data" |
No | Unknown | Unknown | Yes | Unknown |
| kGSSMSCapability "sms" |
No | Yes | Yes | No | Yes |
| kGSCameraCapability "still-camera" |
No | Yes | Yes | No | Yes |
| kGSVideoCameraCapability "video-camera" |
No | No | Yes | No | Yes |
| kGSAutoFocusCameraCapability "auto-focus-camera" |
No | No | Yes | No | Yes |
| kGSH264EncoderCapability "h264-encoder" |
No | No | Yes | Yes | Yes |
| kGSWiFiCapability "wifi" |
Yes | Yes | Yes | Yes | Yes |
| kGSAccelerometerCapability "accelerometer" |
Yes | Yes | Yes | Yes | Yes |
| kGSMagnetometerCapability "magnetometer" |
No | No | Yes | Yes | Yes |
| kGSGPSCapability "gps" |
No | Yes | Yes | No | Yes |
| kGSLocationServicesCapability "location-services" |
Yes | Yes | Yes | Yes | Yes |
| kGSMicrophoneCapability "microphone" |
No | Yes | Yes | Yes | Yes |
| kGSPeer2PeerCapability "peer-peer" |
No | No | Yes | Yes | Yes |
| kGSOpenGLES1Capability "opengles-1" |
Yes | Yes | Yes | Yes | Yes |
| kGSOpenGLES2Capability "opengles-2" |
No | No | Yes | Yes | Yes |
| kGSARMV6ExecutionCapability "armv6" |
Yes | Yes | Yes | Yes | Yes |
| kGSARMV7ExecutionCapability "armv7" |
No | No | Yes | Yes | Yes |
| kGSDisplayPortCapability "display-port" |
No | No | No | Yes | Yes |
| kGSContainsCellularRadioCapability "contains-cellular-radio" |
No | Unknown | Unknown | Yes | Unknown |
| kGSVolumeButtonCapability "volume-buttons" |
No | Yes | Yes | Yes | Yes |
| kGSRingerSwitchCapability "ringer-switch" |
No | Yes | Yes | No | Yes |
| kGSPiezoClickerCapability "piezo-clicker" |
Yes | No | No | No | No |
| kGSBluetoothCapability "bluetooth" |
No | Yes | Yes | Yes | Yes |
| kGSUnifiedIPodCapability "unified-ipod" |
No | Yes | Yes | No | Yes |
| kGSYouTubeCapability "youtube" |
Yes | Yes | Yes | Yes | Yes |
| kGSYouTubePluginCapability "youtubePlugin" |
Yes | Yes | Yes | Yes | Yes |
| kGSGreenTeaDeviceCapability[1] "green-tea" |
No | No | Yes | No | No |
| kGSNotGreenTeaDeviceCapability[1] "not-green-tea" |
Yes | Yes | Yes | Yes | Yes |
| kGSInternationalSettingsCapability "international-settings" |
Yes | Yes | Yes | Yes | Yes |
| kGSPlatformStandAloneContactsCapability "stand-alone-contacts" |
Yes | Yes | Yes | Yes | Yes |
| kGSDelaySleepForHeadsetClickCapability "delay-sleep-for-headset-click" |
No | Yes | No | No | No |
| kGSLaunchApplicationsWhileAnimatingCapability "launch-applications-while-animating" |
No | No | Yes | Yes | Yes |
| kGSLoadThumbnailsWhileScrollingCapability "load-thumbnails-while-scrolling" |
No | No | Yes | Yes | Yes |
| kGSSensitiveUICapability "sensitive-ui" |
No | Unknown | Unknown | Unknown | Unknown |
| kGSAppleInternalInstallCapability "apple-internal-install" |
No | No | No | No | No |
| kGSHasAllFeaturesCapability "all-features" |
Yes | Yes | Yes | Yes | Yes |
| kGSNikeIpodCapability "nike-ipod" |
No | No | Yes | No | Yes |
| kGSApplicationInstallationCapability "applicationInstallation" |
Yes | Yes | Yes | Yes | Yes |
| kGSVoiceControlCapability "voice-control" |
No | No | Yes | No | Yes |
| kGSProximitySensorCapability "proximity-sensor" |
No | Yes | Yes | No | Yes |
| kGSGasGaugeBatteryCapability[2] "gas-gauge-battery" |
No | No | Yes | Yes | Yes |
| kGSAccessibilityCapability "accessibility" |
No | No | Yes | Yes | Yes |
| kGSMMSCapability "mms" |
No | No | Yes | No | Yes |
| kGSEncryptedDataPartitionCapability "encrypted-data-partition" |
No | No | Yes | Yes | Yes |
| kGSEncodeAACCapability "encode-aac" |
No | No | Yes | Unknown | Yes |
| kGS720pPlaybackCapability "720p" |
No | No | No | Yes | Yes |
| kGSDisplayFCCLogosViaSoftwareCapability "fcc-logos-via-software" |
No | No | Yes | Yes | Yes |
| kGSHideNonDefaultApplicationsCapability "hide-non-default-apps" |
No | No | No | Yes | No |
| kGSWildcatCapability[3] "wildcat" |
No | No | No | Yes | No |
| kGSDataPlanCapability "data-plan" |
No | Unknown | Unknown | Yes | Unknown |
| kGSCameraFlashCapability "camera-flash" |
No | No | No | No | Yes |
| kGSCanRasterizeEfficientlyCapability "can-rasterize-efficiently" |
Unknown | Unknown | Unknown | Unknown | Unknown |
| kGSFrontFacingCameraCapability "front-facing-camera" |
No | No | No | No | Yes |
| kGSHiDPICapability "horiz" |
No | No | No | No | Yes |
| kGSIOSurfaceBackedImagesCapability "io-surface-backed-images" |
No | No | Yes | Unknown | Yes |
| kGSMultitaskingCapability "multitasking" |
No | No | Yes | No | Yes |
| kGSVeniceCapability[4] "venice" |
No | No | No | No | Yes |
| kGSTelephonyMaximumGeneration "telephony-maximum-generation" |
0 | 2.5 | 3.5 | Unknown | 3.5 |
| kGSDeviceNameString "device-name" |
iPod | iPhone | iPhone | iPad | iPhone |
| kGSMarketingNameString "marketing-name" |
iPod Touch | iPhone | iPhone 3GS | iPad | iPhone |
| kGSScreenDimensionsCapability[5] "screen-dimensions" |
320 × 480 | 320 × 480 | 320 × 480 | 768 × 1024 | 640 × 960 |
References
- ↑ 1.0 1.1 "Green-Tea" is a code name for devices sold in China. Green-Tea devices have restricted access to various applications e.g. Maps.
- ↑ Gas-gauge capability allows accurate monitoring of the battery level
- ↑ "Wildcat" is the codename of iPad.
- ↑ "Venice" is used to determine if video conferencing is allowed. It is not known what Venice stands for.
- ↑ This capability is a dictionary with 4 members. Only width and height are shown here.
