Final answer:
The ntohl() function is used to convert long integers from network to host byte order, commonly required in network programming for data consistency.
Step-by-step explanation:
The function you use to convert a long integer in network byte order to the machine byte order is ntohl(). This function stands for "Network to Host Long", which takes an uint32_t number in network byte order (which is big-endian) and converts it to the host's native byte order, which is typically little-endian on modern home computers. The use of ntohl() is necessary for networked applications where data interchange between heterogeneous systems with different byte orders is required.