PSEND(3PVM)							  PVM Version 3.4						       PSEND(3PVM)

NAME

       pvm_psend - Pack and send data in one call.

SYNOPSIS

       C    int info = pvm_psend( int tid, int msgtag, char *buf,
				  int len, int datatype )

       Fortran	 call pvmfpsend( tid, msgtag, buf, len, datatype,
			       info )

PARAMETERS

       tid     Integer task identifier of destination process.

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

       buf     Pointer to a buffer to send.

       len     Length of buffer (in multiple of data type size).

       datatype
	       Type of data to which buf points (see below).

       info    Integer status code returned by the routine.

DESCRIPTION

       The  routine  pvm_psend	takes  a pointer to a buffer buf its length len and its data type datatype and sends this data directly to the PVM
       task identified by tid.	msgtag is used to label the content of the message.  If pvm_psend is successful, info will be  0.  If  some  error
       occurs then info will be < 0.

       pvm_psend data can be received by pvm_precv, pvm_recv, pvm_trecv, or pvm_nrecv.

       The  pvm_psend  routine is asynchronous.  Computation on the sending processor resumes as soon as the buffer is safe for reuse.	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.

       In  C  the  datatype parameter must be one of the following, depending on the type of data to be sent: [Version 3.3.0 - This parameter only
       determines message length, not data conversion.	It only sends raw bytes]
	   datatype    Data Type
	   PVM_STR     string
	   PVM_BYTE    byte
	   PVM_SHORT   short
	   PVM_INT     int
	   PVM_FLOAT   real
	   PVM_CPLX    complex
	   PVM_DOUBLE  double
	   PVM_DCPLX   double complex
	   PVM_LONG    long integer
	   PVM_USHORT  unsigned short int
	   PVM_UINT    unsigned int
	   PVM_ULONG   unsigned long int

       In Fortran the same data types specified for pack should be used.

       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.

       pvm_psend does not affect the state of the current outgoing message buffer (created by pvm_initsend and used by pvm_send).

WARNINGS

       In some versions of PVM (CM5, I860 and PGON), messages sent using pvm_psend must be received only by pvm_precv, likewise  those	sent  with
       pvm_send  must  be  received by pvm_recv, pvm_nrecv or pvm_trecv.  pvm_psend is not compatible with pvm_recv (nor pvm_send with pvm_precv).
       In addition, pvm_probe is not interoperable with pvm_psend.

       This problem occurs because nonstandard message headers are used for efficiency in the pvm_psend function.  In the generic Unix version	of
       PVM, the calls are fully interoperable.

       The message tag space is shared between pvm_send and pvm_psend, so you must be careful to avoid selecting the wrong message (for example by
       using a wildcard to match the message).

EXAMPLES

       C:
	   info = pvm_psend( tid, msgtag, array, 1000, PVM_FLOAT );

       Fortran:
	   CALL PVMFPSEND( TID, MSGTAG, BUF, CNT, REAL4, INFO )

ERRORS

       These error conditions can be returned by pvm_psend

       PvmBadParam
	      giving an invalid tid, msgtag, or datatype.

       PvmSysErr
	      pvmd not responding.

SEE ALSO

       pvm_precv(3PVM), pvm_send(3PVM)

								  15 March, 1994						       PSEND(3PVM)