TestOut Linux Pro Practice Test

The command to check space used by a specific directory is "du -sh". The "du" command stands for "disk usage," and it's specifically designed to estimate file space usage. The "-s" option provides a summary, displaying only the total space used by the specified directory rather than listing space usage for each file and subdirectory within it. The "-h" option makes the output human-readable, meaning it will display the sizes in a format that is easier to interpret, such as KB, MB, or GB.

This command is particularly useful when you want to quickly see how much space a directory is consuming without delving into the details of its contents. In contrast, the other options focus on different aspects of system monitoring. For example, "df -h" shows the overall disk space used on all mounted filesystems, "stat" provides detailed information about a specific file or filesystem, and "free" displays memory usage rather than disk usage. Thus, "du -sh" is indeed the most appropriate choice for checking space used by a specific directory.