In Unix like operating systems, which of the following are system calls related to process management?

Introduction / Context:
Process management is a core responsibility of any operating system. Unix like kernels expose process management functionality through system calls that user programs invoke when they need to create processes, replace program images, or query process relationships. Recognizing which functions are true system calls and how they relate to processes is an important exam skill.

Given Data / Assumptions:

• The environment is a Unix like operating system such as Linux.
• System calls provide the interface between user programs and the kernel.
• Functions like fork, exec, and getppid are available to user programs through standard libraries.

Concept / Approach:
The fork system call creates a new process by duplicating the calling process. It is the primary mechanism for process creation and is central to the Unix process model. The exec family of system calls, such as execl and execv, replace the current process image with a new program, preserving the process identifier but changing code and data. The getppid system call returns the process identifier of the parent of the calling process, allowing programs to query process relationships. All three are related to process management and are implemented as system calls that transfer control to the kernel.

Step-by-Step Solution:
Step 1: Consider fork(). It deals directly with creating a new process, so it is clearly a process management system call.Step 2: Consider exec(). It loads a new program into the current process, which is also part of managing processes and program execution.Step 3: Consider getppid(). It allows a process to obtain the identifier of its parent process, which relates to the process hierarchy.Step 4: Each of these functions triggers a transition from user mode to kernel mode to perform process related operations.Step 5: Since all three are system calls connected to process management, the correct option is that all of the above are process management system calls.

Verification / Alternative check:
Consulting Unix manual pages shows that fork, exec, and getppid are all documented as system calls. Their man pages describe their role in creating processes, executing programs, and retrieving parent process identifiers. Textbooks on operating systems also list them in chapters on processes and process control, not in unrelated sections such as file management or networking.

Why Other Options Are Wrong:
Any option that names only one or two of these functions would be incomplete, because all three relate to process management.Options omitting exec would miss the crucial step of loading a new program into a process.Options omitting getppid would overlook an important call for querying process relationships.

Common Pitfalls:
One pitfall is to think that only calls that create or destroy processes count as process management. In reality, reading process identifiers, changing program images, and managing process attributes are also process management operations. Another mistake is to assume that functions exposed in libraries are always pure user level routines. Some are thin wrappers around system calls that enter the kernel to perform privileged actions.

Final Answer:
The correct answer is All of the above.