Write a program in C that uses fork ( )

The parent should read the first line of the input file. Once it has read that line, it should go into a loop based on that number with each iteration of the loop forking off a copy that will then process the next two lines. Once that child has finished its work, it will write some data to an output file and then terminate.

As the parent detects its child has terminated, it should perform another iteration of the loop until done. After all children have terminated, the parent will write the PIDs of all of its children that it launched, as well as its own PID to the output file.

When a child process starts, it should read the next line of the file, which will tell it how many numbers to read afterwards. We see in our example file that the first forked child would read a 6. It should then read that number of integers and put them into a stack. After putting all of the numbers into a stack, the child should write its PID to the output file, followed by those numbers in reverse order. For example:

Input file sample:

3

6

3 6 107 8 1 3 7

4

1 3 50 4

7

5 3 5 2 8 9 1

Output file sample:

130: 7 3 1 8 107 6 3

136: 4 50 3 1

145: 1 9 8 2 5 3 5

All children were: 130 136 145