Section1

Answer the following questions

Using the file input.c

Code:

#include #include "string.h"

int main(int argc, char* argv[]) { int i, j, k; int x[1000];

for(i = 0; i < 10000; ++i){ x[i] = i; }

printf("Enter integer in 0..9999: "); scanf("%d", k);

tester(x, k); }

int tester(int* c, int k) { printf("x[%d] = %d ", k, c[k]); }

1) Creat a Makefile to compile the program

a) Are there any warnings?

b) What is the difference if we add the argument "-Wall" to the compilation ? Modify the Makefile to include the "-Wall" argument.

2) Execute the program. Is there any error ?

3)Open the program with the gdb. What do you have to do first ?

a) Run the program inside gdb. What do you have to do first ?

b) Insert a breakpoint to the main function and run the program again.

c) Choose which command helps you find any mistakes (next, step, continue)

4 Identify the exact lines of the errors and the messages that the gdb prints. Find and correct these errors

Section 2

Write a program that:

1) Asks form the user an integer number N (N>10)

2) Creates N processes that:

a) Each process prints its own PID

b) Each process prints the current time (Tip: check the C date and time funcations)

3) The parent process should print its own ID

4) Run the program 5 times and keep the output. Is it different in some cases?

Explain why this happens

5) Are the PIDs of the processes the same each time you execute the program ?

6) What is the maximum limit to the number of processes possible in a Unix system ? Verify with your program