System Information

Declared in: be/kernel/OS.h

Library: libroot.so

The following functions, types, and structures convey information about the system, such as the number of CPUs, when the kernel was built, and whether your computer is on fire.

System Info Functions

get_system_info()

	status_t get_system_info(system_info *info)

The get_system_info() function tells you more than you want to know about the physical capacities of your computer and other statistics of your operating system. The function copies this information into the system_info argument info. You must allocate info before passing it in.

RETURN CODES

get_system_info() always returns B_OK.

is_computer_on()

	int32 is_computer_on(void)

Returns 1 if the computer is on. If the computer isn't on, the value returned by this function is undefined.

is_computer_on_fire()

	double is_computer_on_fire(void)

Returns the temperature of the motherboard if the computer is currently on fire. If the computer isn't on fire, the function returns some other value.

System Info Structures and Constants

cpu_info

	typedef struct {       bigtime_t active_time;       } cpu_info

The cpu_info structure provides information about your computer's CPU(s). You retrieve the structure by looking in the cpu_infos field of the system_info structure. The cpu_infos field is an array that contains one cpu_info structure for each CPU on your motherboard.

Field	Meaning
active_time	The number of microseconds the CPU has spent doing useful work (i.e. not busy waiting) since the machine was booted.

cpu_type

typedef enum cpu_types {       B_CPU_PPC_601,       B_CPU_PPC_603,       B_CPU_PPC_603e,       B_CPU_PPC_604,       B_CPU_PPC_604e,       B_CPU_PPC_750,       B_CPU_PPC_686,       B_CPU_AMD_29K,       B_CPU_X86, Obsolete       B_CPU_MC6502,       B_CPU_Z80,       B_CPU_ALPHA,       B_CPU_MIPS,       B_CPU_HPPA,       B_CPU_M68K,       B_CPU_ARM,       B_CPU_SH,       B_CPU_SPARC,              B_CPU_INTEL_X86 = 0x1000,       B_CPU_INTEL_PENTIUM,       B_CPU_INTEL_PENTIUM75,       B_CPU_INTEL_PENTIUM_486_OVERDRIVE,       B_CPU_INTEL_PENTIUM_MMX,       B_CPU_INTEL_PENTIUM_MMX_MODEL_4,       B_CPU_INTEL_PENTIUM_MMX_MODEL_8,       B_CPU_INTEL_PENTIUM75_486_OVERDRIVE,       B_CPU_INTEL_PENTIUM_PRO,       B_CPU_INTEL_PENTIUM_II,       B_CPU_INTEL_PENTIUM_II_MODEL_3,       B_CPU_INTEL_PENTIUM_II_MODEL_5,       B_CPU_INTEL_CELERON,       B_CPU_INTEL_PENTIUM_III,              B_CPU_AMD_X86 = 0x1100,       B_CPU_AMD_K5_MODEL0,       B_CPU_AMD_K5_MODEL1,       B_CPU_AMD_K5_MODEL2,       B_CPU_AMD_K5_MODEL3,       B_CPU_AMD_K6_MODEL6,       B_CPU_AMD_K6_MODEL7,       B_CPU_AMD_K6_MODEL8,       B_CPU_AMD_K6_2,       B_CPU_AMD_K6_MODEL9,       B_CPU_AMD_K6_III,       B_CPU_AMD_ATHLON_MODEL1,              B_CPU_CYRIX_X86 = 0x1200,       B_CPU_CYRIX_GXm,       B_CPU_CYRIX_6x86MX,              B_CPU_IDT_X86 = 0x1300,       B_CPU_IDT_WINCHIP_C6,       B_CPU_IDT_WINCHIP_2,              B_CPU_RISE_X86 = 0x1400,       B_CPU_RISE_mP6       } cpu_type;

The B_X86_CPU constant is obsolete. All x86 CPUs are represented by specific vendor/model constants.

These constants represents different CPU vendors and models. To retrieve the constant that represents the CPU(s) that your computer uses, look in the cpu_type field of the system_info structure.

Note that the x86 types are grouped by vendor, where the vendor is identified by the high word, and the model by the low word. Each vendor has its own cpu_type constant, as indicated by the explicit values in the list above. If you're only interested in the vendor, mask the cpu_type value with B_CPU_X86_VENDOR_MASK, thus:

   system_info sysinfo;
   get_system_info( &sysinfo );
   
   switch ( sysinfo.cpu_type & B_CPU_X86_VENDOR_MASK ) {
      case B_CPU_INTEL_X86: ...
      case B_CPU_AMD_X86: ...
      case B_CPU_CYRIX_x86: ...
      case B_CPU_IDT_X86: ...
      case B_CPU_RISE_X86: ...
      default:
      /* Not x86. */
   }

B_CPU_X86_VENDOR_MASK

	B_CPU_X86_VENDOR_MASK

You mask your machine's cpu_type value with this constant to retrieve the CPU's vendor id (which is also a cpu_type value). If the CPU isn't an breed of x86, applying the mask will yield 0. See the cpu_type description for an example.

machine_id

	typedef int32 machine_id[2]; Currently unused

machine_id is a 64-bit number (encoded as two 32-bit numbers) that uniquely identifies this specific computer. The id number is returned as the id field (currently unused) of the system_info structure.