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.Dd January 22, 2015
.Dt KINFO 3
.Os
.Sh NAME
.\".Nm cputime_pcpu_statistics ,
.Nm kinfo_get_cpus ,
.Nm kinfo_get_files ,
.Nm kinfo_get_maxfiles ,
.Nm kinfo_get_net_rtstatistics ,
.Nm kinfo_get_openfiles ,
.Nm kinfo_get_sched_cputime ,
.Nm kinfo_get_sched_hz ,
.Nm kinfo_get_sched_profhz ,
.Nm kinfo_get_sched_stathz ,
.Nm kinfo_get_tty_tk_nin ,
.Nm kinfo_get_tty_tk_nout ,
.Nm kinfo_get_vfs_bufspace
.\".Nm route_pcpu_statistics
.Nd information about the running kernel
.Sh LIBRARY
.Lb libkinfo
.Sh SYNOPSIS
.In kinfo.h
.Ft int
.Fn kinfo_get_files "struct kinfo_file **file_buf" "size_t *len"
.Ft int
.Fn kinfo_get_maxfiles "int *maxfiles"
.Ft int
.Fn kinfo_get_openfiles "int *openfiles"
.Ft int
.Fn kinfo_get_net_rtstatistics "struct rtstatistics *rts"
.Ft int
.Fn kinfo_get_cpus "int *ncpus"
.Ft int
.Fn kinfo_get_sched_cputime "struct kinfo_cputime *cputime"
.Ft int
.Fn kinfo_get_sched_hz "int *hz"
.Ft int
.Fn kinfo_get_sched_profhz "int *profhz"
.Ft int
.Fn kinfo_get_sched_stathz "int *stathz"
.Ft int
.Fn kinfo_get_tty_tk_nin "uint64_t *tk_nin"
.Ft int
.Fn kinfo_get_tty_tk_nout "uint64_t *tk_nout"
.Ft int
.Fn kinfo_get_vfs_bufspace "long *bufspace"
.\".Ft void
.\".Fn cputime_pcpu_statistics "struct kinfo_cputime *percpu" "struct kinfo_cputime *total" "int ncpu"
.\".Ft void
.\".Fn route_pcpu_statistics "struct rtstatistics *percpu" "struct rtstatistics *total" "int ncpu"
.Sh DESCRIPTION
.Ss File Information
The
.Fn kinfo_get_files
function returns the kernel's file table as a pointer to an array of
.Vt kinfo_file
structures in the
.Fa file_buf
argument.
The number of elements in the array is returned in
.Fa len .
It is the caller's responsibility to
.Fn free
the array.
.Pp
The
.Fn kinfo_get_maxfiles
and
.Fn kinfo_get_openfiles
functions return the maximum number of files and the number of open files in the
.Fa maxfiles
and
.Fa openfiles
arguments, respectively.
.Ss Networking Information
The
.Fn kinfo_get_net_rtstatistics
function retrieves routing statistics from the kernel and fills out a
.Vt struct rtstatistics ,
a pointer to which has to be specified by the caller in
.Fa rts .
.Ss Scheduling/Time Information
The
.Fn kinfo_get_cpus
function returns the number of active CPUs in the
.Fa ncpus
argument.
.Pp
The
.Fn kinfo_get_sched_cputime
function retrieves CPU time statistics from the kernel and fills out a
.Vt struct kinfo_cputime ,
a pointer to which has to be specified by the caller in
.Fa cputime .
.Pp
The
.Fn kinfo_get_sched_hz ,
.Fn kinfo_get_sched_profhz ,
and
.Fn kinfo_get_sched_stathz
functions retrieve system clock information from the kernel and return the
.Fa ci_hz ,
.Fa ci_profhz ,
and
.Fa ci_stathz
fields of
.Vt struct kinfo_clockinfo
in the
.Fa hz ,
.Fa profhz ,
and
.Fa stathz
arguments, respectively.
.Ss TTY Information
The
.Fn kinfo_get_tty_tk_nin
and
.Fn kinfo_get_tty_tk_nout
functions return the total number of characters which were input and output
on the system's TTYs in the
.Fa tk_nin
and
.Fa tk_nout
arguments, respectively.
.Ss VFS Information
The
.Fn kinfo_get_vfs_bufspace
function returns the maximum amount of memory available for VFS buffers in the
.Fa bufspace
argument.
.\".Ss Per CPU Accumulators
.\".Fn cputime_pcpu_statistics
.\".Fn route_pcpu_statistics
.Sh RETURN VALUES
.Rv -std
.Sh ERRORS
The
.Fn kinfo_get_cpus ,
.Fn kinfo_get_maxfiles ,
.Fn kinfo_get_openfiles ,
.Fn kinfo_get_sched_hz ,
.Fn kinfo_get_sched_profhz ,
.Fn kinfo_get_sched_stathz ,
.Fn kinfo_get_tty_tk_nin ,
.Fn kinfo_get_tty_tk_nout ,
and
.Fn kinfo_get_vfs_bufspace
functions can fail with the errors documented in
.Xr sysctlbyname 3 .
.Pp
The
.Fn kinfo_get_files ,
.Fn kinfo_get_net_rtstatistics ,
and
.Fn kinfo_get_sched_cputime
functions will fail if:
.Bl -tag -width Er
.It Bq Er ENOMEM
Insufficient memory was available.
.El
.Sh SEE ALSO
.\".Xr kcore 3 ,
.Xr kvm 3
.Sh HISTORY
The
.Nm kinfo
library first appeared in
.Dx 1.2 .
.Sh AUTHORS
.An "Joerg Sonnenberger"