## uncheck
- https://manpages.debian.org/testing/manpages/proc.5.en.html
- https://manpages.debian.org/testing/manpages/procfs.5.en.html
- https://linux.die.net/man/5/proc
- https://www.kernel.org/doc/Documentation/filesystems/proc.txt
- https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/deployment_guide/ch-proc
- https://www.unix.com/man-page/suse/5/proc/
- http://man7.org/linux/man-pages/man5/proc.5.html
## working
- https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/5/html/deployment_guide/ch-proc
## done