.\" $Id: pvm_reg_rm.3,v 1.1 1996/09/23 22:06:04 pvmsrc Exp $
.TH REG_RM 3PVM "4 March, 1994" "" "PVM Version 3.4"
.SH NAME
pvm_reg_rm \- Register task as PVM resource manager.

.SH SYNOPSIS
.nf
.ft B
C	#include <pvmsdpro.h>

	int cc = pvm_reg_rm( struct pvmhostinfo **hip )
.br
	struct pvmhostinfo {
.br
		int  hi_tid;
.br
		char *hi_name;
.br
		char *hi_arch;
.br
		int  hi_speed;
.br
	};
.br

Fortran	Not Available
.fi

.SH PARAMETERS
.IP hostp
Returns
pointer to a pvmhostinfo structure which contains
information about the master host.

.SH DESCRIPTION

Registers the calling task as a PVM task and slave host manager.
This
means it intercepts certain libpvm calls from other tasks
in order to have a say in scheduling policy.
The resource manager will asynchronously receive messages from tasks
containing requests for service,
as well as messages from pvmds notifying it of system failures.

Before you start using this function,
be warned that it's not a trivial thing,
i.e. you can't just call it to turn off the default round-robin task
assignment.
Rather,
it allows you to write your own resource manager and hook it to PVM.

To understand what the following messages mean,
you should refer to the PVM source code and/or user guide section
on implementation;
There's just too much to say about them.

When one of the following libpvm functions is called in a task with
resource manager set,
the given message tag is sent to to resource manager.

.ta 4 26 44
.nf
	\fILibpvm call	RM message	Normal message\fR
	pvm_addhosts()	SM_ADDHOST	TM_ADDHOST
	pvm_config()	SM_CONFIG	TM_CONFIG
	pvm_delhosts()	SM_DELHOST	TM_DELHOST
	pvm_notify()	SM_NOTIFY	TM_NOTIFY
	pvm_spawn()	SM_SPAWN	TM_SPAWN
	pvm_tasks()	SM_TASK	TM_TASK
	pvm_reg_rm()	SM_SCHED	TM_SCHED
.fi

The resource manager must in turn compose the following messages and send
them to the pvmds:

.ta 4 22
.nf
	\fIRM message	Normal message\fR
	SM_EXEC	DM_EXEC
	SM_EXECACK	DM_EXECACK
	SM_ADD	DM_ADD
	SM_ADDACK	DM_ADDACK
	SM_HANDOFF	(none - change of resource manager)
.fi

The following messages are sent asynchronously to the resource manager by
the system:

.nf
	\fIRM message	Meaning\fR
	SM_TASKX	notify of task exit/fail
	SM_HOSTX	notify of host delete/fail
.fi

The resource manager task
must use pvm_setopt(PvmResvTids, 1) to allow sending reserved messages.
Messages should be packed using encoding \fIPvmDataDefault\fR to
ensure they can be unpacked anywhere in the system.

pvm_reg_rm()
returns PvmOk when successful.

.SH SEE ALSO
pvm_addhosts(3PVM),
pvm_config(3PVM),
pvm_delhosts(3PVM),
pvm_notify(3PVM),
pvm_spawn(3PVM),
pvm_tasks(3PVM)