Need help with fork, forking multiple childs and shared memory Post: 302338619

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Top Forums Programming Need help with fork, forking multiple childs and shared memory Post 302338619 by helpmeforlinux on Tuesday 28th of July 2009 11:55:21 AM

07-28-2009

Registered User

Need help with fork, forking multiple childs and shared memory

Hi all,

I m writing an application, where i need to fork multiple childs and those child should handle particular task given to them.

More descriptive.

For example, suppose i have 4 Network, each network has multiple nodes. Now on the basis of network child should be forked and these child will again fork multiple childs on the basis of nodes.

It like
Main Prg
|
--------------------------------------------
Main-Child1 Main-Child2 Main-Child3 Main-Child4
--------------------------------------------------------------------
MC1-1 MC2-1 MC3-1 MC4-1
MC1-2 MC2-2 MC4-2
MC1-3 MC2-3 MC4-3
MC1-4 MC4-4
MC4-5
MC4-6

Now in above diagram there can be more main child depending on the network size and there can me more main-childs child depending on the node in that main-child network. and the lowest level child will be performing some task given to it,its similar task that are other lower child are doing but the difference is the type of data they are provided.

How do i use a shared memory or pipes or kind of IPC to communicate between main-child to its child and from main prg to main-childs to provide some task info to lower level childs.

I have exercised for this and i tried simple program that creates multiple childs. I just want that if any body address me for this scenario that how can i accomplish the above , or any test program any body can give for above scenario.

Thanks in advance.

helpmeforlinux

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LEARN ABOUT HPUX

list_child

list child(1m)															    list child(1m)

NAME

       list child - Displays a list of all the child pointers whose names match the specified child name

SYNOPSIS

       cdscp list child child-name [with attribute-name = attribute-value]

ARGUMENTS

       The full name of a specific child pointer.  The last simple name can contain wildcard characters.  The name of a particular attribute.  The
       value of a particular attribute.

DESCRIPTION

       The list child command displays a list of all the child pointers whose names match the specified child name.  The last simple name can con-
       tain  wildcard  characters.   You  can  use  a  with  attribute-name  = attribute-value clause to limit output only to child pointers whose
       attributes have values equal to the specified values.  A space must precede and follow the = (equals sign).

   Privilege Required
       You must have read permission to the directory that stores the child pointer.  If you use a with attribute-name = attribute-value clause in
       the command, you also need read or test permission to the selected child pointers.

NOTE

       This command is replaced at Revision 1.1 by the dcecp command and may not be provided in future releases of DCE.

EXAMPLE

       The following command displays a list of all the child pointers named in the /.:/sales directory:

       cdscp> list child /.:/sales/*

			       LIST
			      CHILD   /.../abc.com/sales
				 AT   1991-10-15-15:56:00 Q1 Q2 Q3 Q4

RELATED INFORMATION

       Commands: create child(1m), delete child(1m), show child(1m)

																    list child(1m)

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