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RECV(3PVM)			PVM Version 3.4			    RECV(3PVM)

NAME
       pvm_recv	- Receive a message.

SYNOPSIS
       C    int	bufid =	pvm_recv( int tid, int msgtag )

       Fortran	 call pvmfrecv(	tid, msgtag, bufid )

PARAMETERS
       tid     Integer	task  identifier  of  sending  process supplied	by the
	       user.

       msgtag  Integer message tag supplied by the user.  msgtag should	be  >=
	       0.

       bufid   Integer	returns	 the  value  of	 the new active	receive	buffer
	       identifier.  Values less	than zero indicate an error.

DESCRIPTION
       The routine pvm_recv blocks the process until a message with label msg-
       tag  has	 arrived  from tid.  pvm_recv then places the message in a new
       active receive buffer, which also clears	the current receive buffer.

       A -1 in msgtag or tid matches anything.	This allows the	user the  fol-
       lowing  options.	  If  tid = -1 and msgtag is defined by	the user, then
       pvm_recv	will accept a message from any process which  has  a  matching
       msgtag.	 If  msgtag = -1 and tid is defined by the user, then pvm_recv
       will accept any message that is sent from process tid.  If tid =	-1 and
       msgtag =	-1, then pvm_recv will accept any message from any process.

       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,  mes-
       sage  A will arrive at task 2 before message B.	Moreover, if both mes-
       sages arrive before task	2 does a receive, then a wildcard receive will
       always return message A.

       If  pvm_recv  is	 successful, bufid will	be the value of	the new	active
       receive buffer identifier.  If some error occurs	then bufid will	 be  <
       0.

       pvm_recv	 is  blocking  which  means  the routine waits until a message
       matching	the user specified tid and msgtag values arrives at the	 local
       pvmd.  If the message has already arrived then pvm_recv returns immedi-
       ately with the message.

       Once pvm_recv returns, the data in the message can be unpacked into the
       user's memory using the unpack routines.

EXAMPLES
       C:
	    tid	= pvm_parent();
	    msgtag = 4 ;
	    bufid = pvm_recv( tid, msgtag );
	    info = pvm_upkint( tid_array, 10, 1	);
	    info = pvm_upkint( problem_size, 1,	1 );
	    info = pvm_upkfloat( input_array, 100, 1 );

       Fortran:
	    CALL PVMFRECV( -1, 4, BUFID	)
	    CALL PVMFUNPACK( INTEGER4, TIDS, 25, 1, INFO )
	    CALL PVMFUNPACK( REAL8, MATRIX, 100, 100, INFO )

ERRORS
       These error conditions can be returned by pvm_recv

       PvmBadParam
	      giving an	invalid	tid value, or msgtag < -1.

       PvmSysErr
	      pvmd not responding.

SEE ALSO
       pvm_bufinfo(3PVM),    pvm_getminfo(3PVM),    pvm_nrecv(3PVM),   pvm_un-
       pack(3PVM), pvm_probe(3PVM), pvm_send(3PVM), pvm_mcast(3PVM)

				30 August, 1993			    RECV(3PVM)

NAME | SYNOPSIS | PARAMETERS | DESCRIPTION | EXAMPLES | ERRORS | SEE ALSO

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