Get Hostname on Linux using C++

In a Linux environment, the hostname serves as an essential identifier for a system on a network. It provides a human-readable label for the machine, making it easier to manage and communicate within a network environment. When working with C++ on Linux, it's often necessary to retrieve the system's hostname programmatically for various applications and networking purposes. This tutorial explains how to get hostname on Linux using C++.

In the following code, the main function begins by declaring a character array. The HOST_NAME_MAX is a system-defined constant representing the maximum length of a hostname. By allocating a buffer of size HOST_NAME_MAX + 1, we ensure that it can accommodate the maximum possible length of a hostname, plus an additional character for the null terminator. This is a common practice in C and C++ to handle strings and ensure they are properly null-terminated to prevent buffer overflow. Next, the gethostname function is called to retrieve the hostname of the system and store it in the hostname array.

#include <iostream>
#include <climits>
#include <unistd.h>

int main()
{
    char hostname[HOST_NAME_MAX + 1];
    gethostname(hostname, HOST_NAME_MAX + 1);

    std::cout << hostname << std::endl;

    return 0;
}

Here's an output example for the provided code snippet:

john-pc