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BCAST(3PVM)			 PVM Version 3.4		     BCAST(3PVM)

NAME
     pvm_bcast	- Broadcasts the data in the active message buffer to a group of
     processes.

SYNOPSIS
     C	  int info = pvm_bcast( char *group, int msgtag )

     Fortran   call pvmfbcast( group, msgtag, info )

PARAMETERS
     group   Character string group name of an existing group.

     msgtag  Integer message tag supplied by the user.	msgtag should be  >=  0.
	     It allows the user's program to distinguish between different kinds
	     of messages .
	     info integer status code returned by the routine.	Values less than
	     zero indicate an error.

DESCRIPTION
     The routine pvm_bcast broadcasts a message stored in the active send buffer
     to all the members of group.  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  distin-
     guished by msgtag.  If pvm_bcast is successful, info will be 0. If some er-
     ror occurs then info 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  broad-
     cast.  Multicasting is not supported by most multiprocessor vendors.  Typi-
     cally  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 some multiprocessors.

EXAMPLES
     C:
	  info = pvm_initsend( PvmDataRaw );
	  info = pvm_pkint( array, 10, 1 );
	  msgtag = 5 ;
	  info = pvm_bcast( "worker", msgtag );

     Fortran:
	  CALL PVMFINITSEND( PVMDEFAULT )
	  CALL PVMFPKFLOAT( DATA, 100, 1, INFO )
	  CALL PVMFBCAST( 'worker', 5, INFO )

ERRORS
     These error conditions can be returned by pvm_bcast

     PvmSysErr
	    pvmd was not started or has crashed.

     PvmBadParam
	    giving a negative msgtag.

     PvmNoGroup
	    giving a non-existent group name.

SEE ALSO
     pvm_joingroup(3PVM)

				 30 August, 1993		     BCAST(3PVM)

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