answer:You can create a child process in Python using the `os` or `subprocess` module. However, the recommended way is to use the `subprocess` module. Here's an example: ```python import subprocess # Create a child process child = subprocess.Popen(['ls', '-l']) # Wait for the child process to finish child.wait() ``` In this example, we create a child process that runs the `ls -l` command. The `wait()` method blocks the parent process until the child process finishes. If you want to run a Python script as a child process, you can use the `subprocess` module like this: ```python import subprocess import sys # Create a child process child = subprocess.Popen([sys.executable, 'child_script.py']) # Wait for the child process to finish child.wait() ``` Replace `'child_script.py'` with the path to your Python script. Alternatively, you can use the `multiprocessing` module to create a child process: ```python import multiprocessing def child_process(): print(This is the child process) if __name__ == '__main__': # Create a child process child = multiprocessing.Process(target=child_process) child.start() # Wait for the child process to finish child.join() ``` In this example, we define a function `child_process()` that runs in the child process. The `if __name__ == '__main__':` block ensures that the child process is created only once.

answer:Your program is correct and accurately demonstrates the creation of a child process using the `fork` system call in C. The use of `getpid` and `getppid` functions to display the process IDs of the parent and child processes is also correct. As you mentioned, the order of execution of the parent and child processes after the `fork` call is not guaranteed, as both processes are scheduled independently by the operating system. This is a fundamental aspect of concurrent programming in Unix-like systems. To demonstrate this non-deterministic behavior, you can add a loop that creates multiple child processes, and observe how the order of the output messages can vary between runs: ```c #include<stdio.h> #include<unistd.h> int main() { pid_t pid; int i; for (i = 0; i < 5; i++) { // create a child process pid = fork(); if (pid < 0) { perror(fork); return 1; } if (pid == 0) { // this is the child process printf(Child process %d: pid = %d, ppid = %dn, i, getpid(), getppid()); return 0; } else { // this is the parent process printf(Parent process: pid = %d, child pid = %dn, getpid(), pid); } } return 0; } ``` Running this program multiple times will show that the order of the output messages can vary, illustrating the concurrent execution of the parent and child processes.

answer:When a parent process terminates before its child process in a Unix system, the child process becomes an orphan process. An orphan process is a process that has no parent process associated with it. Here are the steps that occur when a parent process terminates before its child process: 1. The parent process terminates, either normally (e.g., by calling `exit`) or abnormally (e.g., due to a signal). 2. The child process continues to run and is now considered an orphan process. 3. The orphan process is adopted by the `init` process, which is the process with process ID 1. The `init` process becomes the new parent of the orphan process. 4. The `init` process performs periodic checks on its child processes, including the orphan process. If the orphan process terminates, the `init` process will clean up after it, including releasing any system resources it was using. In terms of the child process's behavior, becoming an orphan process does not affect its execution. The child process continues to run as if its parent process was still alive. However, if the child process tries to communicate with its parent process (e.g., using a pipe or signal), it will fail because the parent process no longer exists. It's worth noting that orphan processes can be problematic in certain situations, such as: * If the parent process was responsible for cleaning up after the child process (e.g., closing files or releasing resources), the child process may leave behind unclosed files or resources. * If the child process was relying on the parent process for input or output, it may hang or terminate unexpectedly. In general, it's a good practice for parent processes to wait for their child processes to finish before terminating, to ensure that the child processes are properly cleaned up and do not become orphan processes. This can be done using the `wait` or `waitpid` system calls.

answer:For the first 8 weeks, Francie receives an allowance of 5 a week, so she saves 8 * 5 = 40 For the next 6 weeks, Francie receives an allowance of 6 a week, so she saves 6 * 6 = 36 In total, Francie saves 40 + 36 = 76 Francie uses half of the money, so she spends 76 / 2 = 38 on new clothes After buying the clothes, Francie has 76 - 38 = 38 remaining She uses the remaining money to buy a video game that costs 35 After buying the video game, Francie has 38 - 35 = 3 remaining 3 The answer is: 3