pvm_reg_tasker(3pvm) [redhat man page]

REG_TASKER(3PVM)						  PVM Version 3.4						  REG_TASKER(3PVM)

NAME

       pvm_reg_tasker - Register task as PVM task starter.

SYNOPSIS

       C    #include <pvmsdpro.h>

	    int cc = pvm_reg_tasker()

       Fortran	 Not Available

DESCRIPTION

       Registers  the  calling	task  as  a  PVM  task starter.  When a tasker is registered with a pvmd, and the pvmd receives a DM_EXEC message,
       instead of fork()ing and exec()ing the task itself, it passes a message to the tasker, which does the dirty work and sends a  message  back
       to the pvmd.

       Note:  If this doesn't make sense, don't worry about it.  This function is for folks who are writing stuff like debugger servers and so on.
       For a more complete explanation of what's going on here, you should refer to the PVM source code and/or user guide section  on  implementa-
       tion; this is only a man page.  That said...

       When the pvmd receives a DM_EXEC message (request to exec new tasks), it searches epath (the PVM executable search path) for the file name.
       If it finds the file, it then either attempts to start the processes (using fork() and exec()) or, if a tasker has registered, sends  it  a
       SM_STTASK message.

       The format of the SM_STTASK message is:
	   int tid		 // of task
	   int flags		 // as passed to spawn()
	   string path		 // absolute path of the executable
	   int argc		 // number of args to process
	   string argv[argc]	 // args
	   int nenv		 // number of envars to pass to task
	   string env[nenv]	 // environment strings

       The  tasker must attempt to start the process when it gets one of these messages.  The tasker doesn't reply to the pvmd if the task is suc-
       cessfully started; the task will reconnect to the pvmd on its own, using the cookie in envar PVMEPID to identify itself to the pvmd.

       The tasker must send a SM_TASKX message to the pvmd when any task that it owns (has started) exits, or if it can't start a particular task.
       The format of the SM_TASKX message is:

	   int tid		 // of task
	   int status		 // the Unix exit status (from wait())
	   int u_sec		 // user time used by the task, seconds
	   int u_usec		 // microseconds
	   int s_sec		 // system time used by the task, seconds
	   int s_usec		 // microseconds

       The  tasker  task  must	use  pvm_setopt(PvmResvTids, 1) to allow sending reserved messages.  Messages should be packed using encoding Pvm-
       DataDefault to ensure they can be unpacked anywhere in the system.

       pvm_reg_tasker() returns PvmOk when successful.

SEE ALSO

       pvm_spawn(3PVM), pvm_tasks(3PVM),

								  16 March, 1994						  REG_TASKER(3PVM)

REG_RM(3PVM)							  PVM Version 3.4						      REG_RM(3PVM)

NAME

       pvm_reg_rm - Register task as PVM resource manager.

SYNOPSIS

       C    #include <pvmsdpro.h>

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

       Fortran	 Not Available

PARAMETERS

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

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 man-
       ager.

	   Libpvm call		 RM message	   Normal message
	   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

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

	   RM message	     Normal message
	   SM_EXEC	     DM_EXEC
	   SM_EXECACK	     DM_EXECACK
	   SM_ADD	     DM_ADD
	   SM_ADDACK	     DM_ADDACK
	   SM_HANDOFF	     (none - change of resource manager)

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

	   RM message	     Meaning
	   SM_TASKX	     notify of task exit/fail
	   SM_HOSTX	     notify of host delete/fail

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

       pvm_reg_rm() returns PvmOk when successful.

SEE ALSO

       pvm_addhosts(3PVM), pvm_config(3PVM), pvm_delhosts(3PVM), pvm_notify(3PVM), pvm_spawn(3PVM), pvm_tasks(3PVM)

								   4 March, 1994						      REG_RM(3PVM)