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KVM_SWAPINFO(3) FreeBSD Library Functions Manual KVM_SWAPINFO(3)
NAME
kvm_getswapinfo - return swap summary statistics for the system
LIBRARY
Kernel Data Access Library (libkvm, -lkvm)
SYNOPSIS
#include <kvm.h>
int
kvm_getswapinfo(kvm_t *kd, struct kvm_swap *, int maxswap, int flags);
DESCRIPTION
The kvm_getswapinfo() function fills an array of kvm_swap structures with
swap summary information for each swap device, for up to maxswap - 1
devices. The number of devices, up to maxswap - 1, is returned. A grand
total of all swap devices (including any devices that go beyond maxswap -
1) is returned in one additional array entry. This entry is not counted
in the return value. Thus, if you specify a maxswap value of 1, the
function will typically return the value 0 and the single kvm_swap
structure will be filled with the grand total over all swap devices. The
grand total is calculated from all available swap devices whether or not
you made room for them all in the array. The grand total is returned.
The flags argument is currently unused and must be passed as 0.
If an error occurs, -1 is returned.
Each swap partition and the grand total is summarized in the kvm_swap
structure. This structure contains the following fields:
char ksw_devname[];
u_int ksw_total;
u_int ksw_used;
int ksw_flags;
Values are in PAGE_SIZE'd chunks (see getpagesize(3)). ksw_flags
contains a copy of the swap device flags.
CACHING
This function caches the nlist values for various kernel variables which
it reuses in successive calls. You may call the function with kd == NULL
to clear the cache.
DIAGNOSTICS
If the swap summary information was unobtainable, -1 is returned;
otherwise, the number of swap devices actually retrieved is returned.
If the name of the swap device does not fit in the static char buffer in
the structure, it is truncated. The buffer is always zero terminated.
SEE ALSO
kvm(3)
FreeBSD 14.2-RELEASE January 2, 2017 FreeBSD 14.2-RELEASE