CPP CPP Interoperability & System Programming 2

Question 1

Which POSIX function creates a new child process?

Accepted Answer

fork()

Answer

fork() creates a new process by duplicating the calling process; the child receives a copy of the parent's address space.

Question 2

What does the mmap() system call do?

Accepted Answer

Maps a file or anonymous region into the process's virtual address space

Answer

mmap() maps a file or anonymous memory region into the virtual address space of the process, enabling efficient file I/O and shared memory.

Question 3

What does write() return when it encounters an error?

Accepted Answer

-1

Answer

Like most POSIX I/O system calls, write() returns -1 on error and sets the global errno to indicate the specific failure.

Question 4

Which signal is delivered to a process when it accesses an invalid memory address?

Accepted Answer

SIGSEGV

Answer

SIGSEGV (segmentation violation) is sent by the kernel when a process attempts to access memory outside its allowed address space.

Question 5

What does the POSIX pipe() function create?

Accepted Answer

A unidirectional IPC channel with a read end and write end

Answer

pipe() creates a pair of file descriptors forming a unidirectional channel: data written to one end can be read from the other.

(CPP) C++ Programming Professional Certificate Practice Test