Which path would you read to obtain CPU information from the proc filesystem?

• A. /proc/loadavg
• B. /proc/meminfo
• C. /proc/cpuinfo
• D. /proc/uptime

Answer: (C)

In Linux, the proc filesystem exposes runtime system details as readable text files. To get CPU information, read the CPU information file: /proc/cpuinfo. This file is organized into blocks, one per processor (or core), especially on systems with multiple cores or hyper-threading. Each block includes fields like processor (the index), vendor_id, model_name, cpuMHz, cache size, and flags that indicate supported features (such as sse, avx, etc.). By inspecting this, you can learn the exact model, speed, number of cores, and capabilities of the CPUs in the system. If you want a quick summary, you can use commands like grep -c ^processor /proc/cpuinfo to count CPUs, or grep 'model name' /proc/cpuinfo to list the models. Other proc files serve different purposes: /proc/loadavg shows system load averages, /proc/meminfo provides memory details, and /proc/uptime shows how long the system has been running.