Mount procfs file system

FreeBSD doesn’t mount procfs file system by default, if you need it, you can mount it yourself:

mount -t procfs proc    /proc

If you want the procfs is automatically mounted at boot time, you can add the following line in /etc/fstab file:

proc         /proc   procfs  rw    0 0  

References:
procfs: Gone But Not Forgotten;
procfs — process file system.