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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  de-
     vices.  The number of devices, up to maxswap - 1, is returned.  A grand to-
     tal  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 cal-
     culated 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;  other-
     wise, 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 ports 15.1		 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+15.1-RELEASE+and+Ports>

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