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SEND(3PVM) PVM Version 3.4 SEND(3PVM)

NAME

pvm_send - Immediately sends the data in the active message buffer.

SYNOPSIS

C	int info = pvm_send( int tid, int msgtag )

Fortran call pvmfsend( tid, msgtag, info )

PARAMETERS

Integer task identifier of destination process.
Integer message tag supplied by the user. msgtag should be >= 0.
Integer status code returned by the routine.

DESCRIPTION

The routine pvm_send sends a message stored in the active send buffer to the PVM process identified by tid. msgtag is used to label the content of the message. If pvm_send is successful, info will be 0. If some error occurs then info will be < 0.

The pvm_send routine is asynchronous. Computation on the sending processor resumes as soon as the message is safely on its way to the receiving processor. This is in contrast to synchronous communication, during which computation on the sending processor halts until the matching receive is executed by the receiving processor.

The PVM model guarantees the following about message order. If task 1 sends message A to task 2, then task 1 sends message B to task 2, message A will arrive at task 2 before message B. Moreover, if both messages arrive before task 2 does a receive, then a wildcard receive will always return message A.

Terminating a PVM task immediately after sending a message or messages from it may result in those messages being lost. To be sure, always call pvm_exit() before stopping.

EXAMPLES

C:
	info = pvm_initsend( PvmDataDefault );
	info = pvm_pkint( array, 10, 1 );
	msgtag = 3 ;
	info = pvm_send( tid, msgtag );

Fortran:
	CALL PVMFINITSEND(PVMRAW, INFO)
	CALL PVMFPACK( REAL8, DATA, 100, 1, INFO )
	CALL PVMFSEND( TID, 3, INFO )

ERRORS

These error conditions can be returned by pvm_send

giving an invalid tid or a msgtag.
pvmd not responding.
no active send buffer. Try pvm_initsend() before send.

SEE ALSO

pvm_initsend(3PVM), pvm_mcast(3PVM), pvm_pack(3PVM), pvm_psend(3PVM), pvm_recv(3PVM)

30 August, 1993