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.
DESCRIPTION¶
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 difference
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)