小编Mal*_*olm的帖子

当我使用此代码时,我收到错误"C99中隐式声明函数'sysctlbyname'无效".我之前使用它,它很好,所以我不知道发生了什么.

我目前正在开发iOS7设备,并使用应用商店中的最新版xcode 5

UIDeviceHardware.m

@interface UIDeviceHardware : NSObject

- (NSString *) platform;
- (NSString *) platformString;

@end

UIDeviceHardware.m

- (NSString *) platform{
    size_t size;
    sysctlbyname("hw.machine", NULL, &size, NULL, 0);
    char *machine = malloc(size);
    sysctlbyname("hw.machine", machine, &size, NULL, 0);
    NSString *platform = [NSString stringWithUTF8String:machine];
    free(machine);
    return platform;
}

- (NSString *) platformString{
    NSString *platform = [self platform];
    if ([platform isEqualToString:@"iPhone1,1"])    return @"iPhone 1G";
    if ([platform isEqualToString:@"iPhone1,2"])    return @"iPhone 3G";
    if ([platform isEqualToString:@"iPhone2,1"])    return @"iPhone 3GS";
    if ([platform isEqualToString:@"iPhone3,1"])    return @"iPhone 4 …