L&T Technology Services C Developer Interview Questions and Answers

Structures in C++ allow for multiple data types to be grouped together, while unions share the same memory space for all members.

• Structures in C++ can hold multiple data types, each with its own memory allocation.

• Unions in C++ share the same memory space for all members, allowing only one member to be active at a time.

• Structures are used when different types of data need to be stored together, while unions are used when only one type of data needs to be stored at a time.

Dynamic memory allocation in C allows for allocating memory at runtime, enabling flexibility in memory usage.

• Dynamic memory allocation is done using functions like malloc(), calloc(), realloc() in C.

• It allows for allocating memory as needed during program execution.

• Dynamic memory allocation helps in managing memory efficiently by allocating and deallocating memory as required.

• Example: int *ptr = (int*)malloc(5 * sizeof(int)); // Allocates memory for an array of 5 integers

To convert a value from Big Endian to Little Endian format, reverse the order of bytes.

• Iterate through the bytes of the value in reverse order

• Swap the positions of each byte to convert from Big Endian to Little Endian

• Example: Big Endian value 0x12345678 becomes Little Endian value 0x78563412

A zombie process is a process that has completed execution but still has an entry in the process table.

• Zombie processes occur when a child process finishes execution before the parent process can collect its exit status.

• Zombie processes consume system resources and should be cleaned up by the parent process using wait() or waitpid() system calls.

• Zombie processes can be identified using tools like ps command in Unix/Linux systems.

• Example: When a parent process forks a child pr...read more

A class for debit, credit and balance check functionalities

• Create a class with member variables for balance

• Add member functions for debit, credit and balance check

• Ensure proper validation and error handling

• Consider using exception handling for errors

IPC stands for Inter-Process Communication, which allows processes to communicate and share data with each other.

• IPC enables processes to exchange data and information with each other.

• Common IPC mechanisms include pipes, message queues, shared memory, and sockets.

• Examples of IPC usage include communication between a parent and child process, or between different processes on a network.

To add an external API to a project, you need to first obtain the API documentation and credentials.

• Obtain API documentation and credentials

• Integrate API into project using appropriate libraries or frameworks

• Test API functionality and handle errors appropriately

Abstract design pattern is a way to define a blueprint for a group of objects with common characteristics.

• It allows creating objects without specifying their concrete classes.

• It promotes loose coupling between classes.

• It is implemented using abstract classes and interfaces.

• Example: Shape is an abstract class and Circle, Square, Triangle are its concrete subclasses.

• Example: JDBC API uses abstract classes and interfaces to provide a common interface for different database vendo...read more