CS220 Homework 9 Due May 9, 2016

Name:

Given the following C program...

	int main(int argc, char **argv) {
		int pid=0, targ, status;
		for (targ=0; targ<argc; targ++) {
			printf("Processing argument: %s\n",argc[targ]);
			if (pid==0) pid=fork();
		}
		while(-1!=wait(&status));
		return 0;
	}
	
If I compile the program into an executable file called "showArgs", and then
invoke the program as "./showArgs a b c"...

1. How many child processes will get forked?

2. How many times will "processing argument b" get printed?

3. In a single process, how many times will "wait" get executed?

There is a new subdirectory in the examples section called "xmp_shell".  Look at that code
(download it and build it if you wish)... Asnwer the following questions based on that
code...

4. Does the code in shell.c support input redirection, output redirection, and background processing?

5. The code in shell.c reaps the return code from background processes in two places... at line 32,
   and at line 36.  Why do we wait in both places?