Section: PVM Version 3.4 (3PVM)
Updated: 30 August, 1993
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pvm_bcast - Broadcasts the data in the active
message buffer to a group of processes.
C int info = pvm_bcast( char *group, int msgtag )
Fortran call pvmfbcast( group, msgtag, info )
Character string group name of an existing group.
Integer message tag supplied by the user.
msgtag should be >= 0.
It allows the user's program to
distinguish between different kinds of messages .
integer status code returned by the routine.
Values less than zero indicate an error.
broadcasts a message stored
in the active send buffer to all the members of
In PVM 3.2 and later the broadcast message is not sent back to the sender.
Any PVM task can call pvm_bcast(), it need not be a member of the group.
The content of the message can be distinguished by
If pvm_bcast is successful,
will be 0. If some error occurs then
will be < 0.
pvm_bcast is asynchronous.
Computation on the sending processor resumes as soon as the message is
safely on its way to the receiving processors. This is in
contrast to synchronous communication, during which computation on
the sending processor halts until a matching receive is
executed by all the receiving processors.
pvm_bcast first determines the tids of the
group members by checking a group data base.
A multicast is performed to these tids.
If the group is changed during a broadcast the change will not
be reflected in the broadcast.
Multicasting is not supported by most multiprocessor vendors.
Typically their native calls only support broadcasting to all
the user's processes on a multiprocessor. Because of this omission,
pvm_bcast may not be an efficient communication method on
info = pvm_initsend( PvmDataRaw );
info = pvm_pkint( array, 10, 1 );
msgtag = 5 ;
info = pvm_bcast( "worker", msgtag );
CALL PVMFINITSEND( PVMDEFAULT )
CALL PVMFPKFLOAT( DATA, 100, 1, INFO )
CALL PVMFBCAST( 'worker', 5, INFO )
These error conditions can be returned by
pvmd was not started or has crashed.
giving a negative msgtag.
giving a non-existent group name.
- SEE ALSO
linux.jgfs.net manual pages