|PROBE(3PVM)||PVM Version 3.4||PROBE(3PVM)|
pvm_probe - Check if message has arrived.
C int bufid = pvm_probe( int tid, int msgtag )
Fortran call pvmfprobe( tid, msgtag, bufid )
The routine pvm_probe checks to see if a message with label msgtag has arrived from tid. If a matching message has arrived pvm_probe returns a buffer identifier in bufid. This bufid can be used with pvm_bufinfo to determine information about the message such as its source and length.
If the requested message has not arrived, then pvm_probe returns with a 0 in bufid. If some error occurs bufid will be < 0.
A -1 in msgtag or tid matches anything. This allows the user the following options. If tid = -1 and msgtag is defined by the user, then pvm_probe will accept a message from any process which has a matching msgtag. If msgtag = -1 and tid is defined by the user, then pvm_probe will accept any message that is sent from process tid. If tid = -1 and msgtag = -1, then pvm_probe will accept any message from any process.
pvm_probe can be called multiple times to check if a given message has arrived yet. After the message has arrived, pvm_recv must be called before the message can be unpacked into the user's memory using the unpack routines.
C: tid = pvm_parent(); msgtag = 4 ; arrived = pvm_probe( tid, msgtag ); if ( arrived ) info = pvm_bufinfo( arrived, &len, &tag, &tid ); else /* go do other computing */ Fortran: CALL PVMFPROBE( -1, 4, ARRIVED ) IF ( ARRIVED .GT. 0 ) THEN CALL PVMFBUFINFO( ARRIVED, LEN, TAG, TID, INFO ) ELSE * GO DO USEFUL WORK ENDIF
These error conditions can be returned by pvm_probe.
pvm_bufinfo(3PVM), pvm_getminfo(3PVM), pvm_nrecv(3PVM), pvm_recv(3PVM), pvm_unpack(3PVM)
|30 August, 1993|