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The host_info
function returns various information about
host. host_info is an array of integers that is supplied by
the caller. It will be filled with the requested information.
host_info_count is supplied as the maximum number of integers in
host_info. On return, it contains the actual number of integers
in host_info. The maximum number of integers returned by any
flavor is HOST_INFO_MAX
.
The type of information returned is defined by flavor, which can be one of the following:
HOST_BASIC_INFO
The function returns basic information about the host, as defined by
host_basic_info_t
. This includes the number of processors, their
type, and the amount of memory installed in the system. The number of
integers returned is HOST_BASIC_INFO_COUNT
. For how to get more
information about the processor, see Processor Interface.
HOST_PROCESSOR_SLOTS
The function returns the numbers of the slots with active processors in
them. The number of integers returned can be up to max_cpus
, as
returned by the HOST_BASIC_INFO
flavor of host_info
.
HOST_SCHED_INFO
The function returns information of interest to schedulers as defined by
host_sched_info_t
. The number of integers returned is
HOST_SCHED_INFO_COUNT
.
The function returns KERN_SUCCESS
if the call succeeded and
KERN_INVALID_ARGUMENT
if host is not a host or flavor
is not recognized. The function returns MIG_ARRAY_TOO_LARGE
if
the returned info array is too large for host_info. In this case,
host_info is filled as much as possible and host_info_count
is set to the number of elements that would be returned if there were
enough room.
A pointer to this structure is returned in host_info by the
host_info
function and provides basic information about the host.
You can cast a variable of type host_info_t
to a pointer of this
type if you provided it as the host_info parameter for the
HOST_BASIC_INFO
flavor of host_info
. It has the following
members:
int max_cpus
The maximum number of possible processors for which the kernel is configured.
int avail_cpus
The number of cpus currently available.
vm_size_t memory_size
The size of physical memory in bytes.
cpu_type_t cpu_type
The type of the master processor.
cpu_subtype_t cpu_subtype
The subtype of the master processor.
The type and subtype of the individual processors are also available
by processor_info
, see Processor Interface.
This is a pointer to a struct host_basic_info
.
A pointer to this structure is returned in host_info by the
host_info
function and provides information of interest to
schedulers. You can cast a variable of type host_info_t
to a
pointer of this type if you provided it as the host_info parameter
for the HOST_SCHED_INFO
flavor of host_info
. It has the
following members:
int min_timeout
The minimum timeout and unit of time in milliseconds.
int min_quantum
The minimum quantum and unit of quantum in milliseconds.
This is a pointer to a struct host_sched_info
.
The host_kernel_version
function returns the version string
compiled into the kernel executing on host at the time it was
built in the character string version. This string describes the
version of the kernel. The constant KERNEL_VERSION_MAX
should be
used to dimension storage for the returned string if the
kernel_version_t
declaration is not used.
If the version string compiled into the kernel is longer than
KERNEL_VERSION_MAX
, the result is truncated and not necessarily
null-terminated.
If host is not a valid send right to a host port, the function
returns KERN_INVALID_ARGUMENT
. If version points to
inaccessible memory, it returns KERN_INVALID_ADDRESS
, and
KERN_SUCCESS
otherwise.
The host_get_boot_info
function returns the boot-time information
string supplied by the operator to the kernel executing on
host_priv in the character string boot_info. The constant
KERNEL_BOOT_INFO_MAX
should be used to dimension storage for the
returned string if the kernel_boot_info_t
declaration is not
used.
If the boot-time information string supplied by the operator is longer
than KERNEL_BOOT_INFO_MAX
, the result is truncated and not
necessarily null-terminated.
Next: Host Time, Previous: Host Ports, Up: Host Interface [Contents][Index]