Chapter 3. The proc File System

Chapter 3. The `proc` File System

3.1. A Virtual File System

3.1.1. Viewing Virtual Files
3.1.2. Changing Virtual Files

3.2. Top-level Files within the proc File System

3.2.1. /proc/apm
3.2.2. /proc/buddyinfo
3.2.3. /proc/cmdline
3.2.4. /proc/cpuinfo
3.2.5. /proc/crypto
3.2.6. /proc/devices
3.2.7. /proc/dma
3.2.8. /proc/execdomains
3.2.9. /proc/fb
3.2.10. /proc/filesystems
3.2.11. /proc/interrupts
3.2.12. /proc/iomem
3.2.13. /proc/ioports
3.2.14. /proc/kcore
3.2.15. /proc/kmsg
3.2.16. /proc/loadavg
3.2.17. /proc/locks
3.2.18. /proc/mdstat
3.2.19. /proc/meminfo
3.2.20. /proc/misc
3.2.21. /proc/modules
3.2.22. /proc/mounts
3.2.23. /proc/mtrr
3.2.24. /proc/partitions
3.2.25. /proc/pci
3.2.26. /proc/slabinfo
3.2.27. /proc/stat
3.2.28. /proc/swaps
3.2.29. /proc/sysrq-trigger
3.2.30. /proc/uptime
3.2.31. /proc/version

3.3. Directories within /proc/

3.3.1. Process Directories
3.3.2. /proc/bus/
3.3.3. /proc/driver/
3.3.4. /proc/fs
3.3.5. /proc/ide/
3.3.6. /proc/irq/
3.3.7. /proc/net/
3.3.8. /proc/scsi/
3.3.9. /proc/sys/
3.3.10. /proc/sysvipc/
3.3.11. /proc/tty/

3.4. Using the sysctl Command

3.5. Additional Resources

3.5.1. Installed Documentation
3.5.2. Useful Websites

The Linux kernel has two primary functions: to control access to physical devices on the computer and to schedule when and how processes interact with these devices. The /proc/ directory — also called the proc file system — contains a hierarchy of special files which represent the current state of the kernel — allowing applications and users to peer into the kernel's view of the system.

Within the /proc/ directory, one can find a wealth of information detailing the system hardware and any processes currently running. In addition, some of the files within the /proc/ directory tree can be manipulated by users and applications to communicate configuration changes to the kernel.