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

       pvm_reg_tasker -	Register task as PVM task starter.

       C    #include <pvmsdpro.h>

	    int	cc = pvm_reg_tasker()

       Fortran	 Not Available

       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,  in-
       stead  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 re-
       fer to the PVM source code and/or user guide section on implementation;
       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 success-
       fully  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 PvmDataDe-
       fault to	ensure they can	be unpacked anywhere in	the system.

       pvm_reg_tasker()	returns	PvmOk when successful.

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

				16 March, 1994		      REG_TASKER(3PVM)


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