Spawn Multiple child using fork()

This is a discussion on Spawn Multiple child using fork() within the Linux Programming forums, part of the Platform Specific Boards category; I am implementing the READERS WRITERS problem in C. I need to spawn multiple readers. I did the following. Code: ...

  1. #1
    Anirban Ghosh
    Join Date
    Jan 2006
    Posts
    278

    Spawn Multiple child using fork()

    I am implementing the READERS WRITERS problem in C.
    I need to spawn multiple readers. I did the following.

    Code:
    #include <sys/types.h>
    #include <unistd.h>
    #include <stdlib.h> 
    #include <stdio.h>
    
    int main()
    {
    	pid_t R1, R2, R3, W1, W2, W3;
    	
    	R1 = fork();
    	R2 = fork();
    	R3 = fork();
    	
    	if(R1 == 0 || R2 == 0 || R3 == 0)
    	{
    		printf("\nI am child ... \n");
    		return 0;
    	}
    	else
    	{
    		printf("\nI am parent ... \n");
    		return 0;
    	}
    	
    	return EXIT_SUCCESS;
    }
    But I am getting weird output.
    I need to print exactly 3 times "I am child ... "
    and only 1 time "I am parent .. "

  2. #2
    and the hat of wrongness Salem's Avatar
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    The child of R1 also creates R2 and R3
    The child of R2 also creates R3

    You have 3 children, and a hand-full of grandchildren as well.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
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  3. #3
    Anirban Ghosh
    Join Date
    Jan 2006
    Posts
    278
    So how shall I create say 3 readers and 3 writers with a common reader and writer function?
    Any help please?

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