HOSTSYNC(3PVM)						       HOSTSYNC(3PVM)

NAME
  pvm_hostsync - Get time-of-day clock from PVM	host.

SYNOPSIS
  C	  #include <sys/time.h>
	  int info = pvm_hostsync( int host, struct timeval *clk,
		  struct timeval *delta	)

  Fortran call pvmfhostsync( host, clksec, clkusec, deltasec, deltausec, info )

PARAMETERS

  host	  TID of host.

  clk	  (or clksec and clkusec) Returns time-of-day clock sample from	host.

  delta	  (or deltasec and deltausec) Returns difference between local clock
	  and remote host clock.

DISCUSSION
  pvm_hostsync samples the time-of day clock of	a host in the virtual machine
  and returns both the clock value and the difference between local and
  remote clocks.

  To reduce the	delta error due	to message transit time, local clock samples
  are taken before and after reading the remote	clock.	Delta is the differ-
  ence between the mean	local clocks and remote	clock.

  Note that the	delta time can be negative.  The microseconds field is always
  normalized to	0..999999, while the sign of the seconds field gives the sign
  of the delta.	 For example:
	  3.25 Sec =  3,250000
	  0	   =  0,0
	  -1 uSec  = -1,999999
	  -1 Sec   = -1,000000
	  -1.1 Sec = -2,999000

  In C,	if clk or delta	is a null pointer, that	parameter is not returned.

ERRORS
  If pvm_hostsync is successful, it returns PvmOk.  These error	conditions
  can be returned by pvm_hostsync
       PvmSysErr      pvmd not responding.
       PvmNoHost      specified	host not in virtual machine.
       PvmHostFail    host is unreachable (and thus possibly failed)

SEE ALSO
  pvm_config(3PVM)