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KVM_SWAPINFO(3)		    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  to-
       tal 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  con-
       tains 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;  oth-
       erwise, 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	termi-
       nated.

SEE ALSO
       kvm(3)

FreeBSD	14.3			January	2, 2017		       KVM_SWAPINFO(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=kvm_getswapinfo&sektion=3&manpath=FreeBSD+14.3-RELEASE+and+Ports>

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