Linux

/proc/{pid}/          #process
/proc/{pid}/exe       #executable, (also for stopped processes)
 
/proc/{pid}/cmdline
/proc/{pid}/environ
/proc/{pid}/fd
/proc/{pid}/cwd       # working directory
/proc/{pid}/net
/proc/{pid}/status
 
# open ports, assume folder /proc/{pid}/
cat net/tcp | awk 'NR>1 {split($2, a, ":"); printf "%d\n", "0x" a[2]}'
cat /net/udp | awk 'NR>1 {split($2, a, ":"); printf "%d\n", "0x" a[2]}'
# connected local ip's
cat /net/arp

timedatectl status
lsmod
iptables-save
mount