MSTAT(3PVM) PVM Version 3.4 MSTAT(3PVM)NAME
pvm_mstat - Returns the status of a host in the virtual machine.
SYNOPSIS
C int mstat = pvm_mstat( char *host )
Fortran call pvmfmstat( host, mstat )
PARAMETERS
host Character string containing the host name.
mstat Integer returning machine status:
value MEANING
PvmOk host is OK
PvmNoHost host is not in virtual machine
PvmHostFail host is unreachable (and thus possibly failed)
DESCRIPTION
The routine pvm_mstat returns the status mstat of the computer named host with respect to running PVM processes. This routine can be used
to determine if a particular host has failed and if the virtual machine needs to be reconfigured. The function pvm_notify() can also be
used to notify the caller that a host has failed.
EXAMPLES
C:
mstat = pvm_mstat( "msr.ornl.gov" );
Fortran:
CALL PVMFMSTAT( 'msr.ornl.gov', MSTAT )
ERRORS
These error conditions can be returned by pvm_mstat
PvmSysErr
pvmd not responding.
PvmNoHost
giving a host name not in the virtual machine.
PvmHostFail
host is unreachable (and thus possibly failed).
SEE ALSO pvm_notify(3PVM), pvm_config(3PVM)
30 August, 1993 MSTAT(3PVM)
Check Out this Related Man Page
ADDHOSTS(3PVM) PVM Version 3.4 ADDHOSTS(3PVM)NAME
pvm_addhosts - Add hosts to the virtual machine.
SYNOPSIS
C int info = pvm_addhosts( char **hosts, int nhost, int *infos )
Fortran call pvmfaddhost( host, info )
PARAMETERS
hosts An array of strings naming the hosts to be added. Pvmd must already be installed and the user must have an account on the speci-
fied hosts.
nhost Integer specifying the length of array hosts.
infos Integer array of length nhost which returns the status for each host. Values less than zero indicate an error, while positive val-
ues are TIDs of the new hosts.
host Character string naming the host to be added.
info Integer status code returned by the routine. Values less than nhost indicate partial failure, and values less than 1 indicate
total failure.
DESCRIPTION
The routine pvm_addhosts adds the computers named in hosts to the configuration of computers making up the virtual machine. The names
should have the same syntax as lines of a pvmd hostfile (see man page for pvmd3): A hostname followed by options of the form xx=y.
If pvm_addhosts is successful, info will be equal to nhost. Partial success is indicated by 0 < info < nhost, and total failure by info <
1. The array infos can be checked to determine which host caused the error.
The Fortran routine pvmfaddhost adds a single host to the configuration with each call. info will be 1 if successful or < 0 if error.
The status of hosts can be requested by the application using pvm_mstat and pvm_config. If a host fails it will be automatically deleted
from the configuration. Using pvm_addhosts a replacement host can be added by the application, however it is the responsibility of the
application developer to make his application tolerant of host failure. Another use of this feature would be to add more hosts as they
become available, for example on a weekend, or if the application dynamically determines it could use more computational power.
EXAMPLES
C:
static char *hosts[] = {
"sparky",
"thud.cs.utk.edu",
};
info = pvm_addhosts( hosts, 2, infos );
Fortran:
CALL PVMFADDHOST( 'azure', INFO )
ERRORS
The following error conditions can be returned by pvm_addhosts:
PvmBadParam
giving an invalid argument value.
PvmAlready
another task is currently adding hosts.
PvmSysErr
local pvmd is not responding.
and in the infos vector:
PvmBadParam
bad hostname syntax.
PvmNoHost
no such host.
PvmCantStart
failed to start pvmd on host.
PvmDupHost
host already configured.
PvmBadVersion
pvmd protocol versions don't match.
PvmOutOfRes
PVM has run out of system resources.
SEE ALSO pvm_pvmd3(1PVM), pvm_delhosts(3PVM), pvm_start_pvmd(3PVM), pvm_config(3PVM), pvm_mstat(3PVM)
22 February, 1994 ADDHOSTS(3PVM)