root@close-grouse:~# ls -l /proc/1/fd
total 0
lrwx------ 1 root root 64 Oct 10 18:56 0 -> /dev/null
lrwx------ 1 root root 64 Oct 10 18:56 1 -> /dev/null
lrwx------ 1 root root 64 Oct 10 18:56 2 -> /dev/null
root@close-grouse:~# lsof -p 1
COMMAND PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
systemd   1 root  cwd    DIR   0,65      140  264 /
systemd   1 root  rtd    DIR   0,65      140  264 /
systemd   1 root  txt    REG   0,65  1577232 2705 /lib/systemd/systemd
systemd   1 root  mem    REG   0,42          2705 /lib/systemd/systemd (path dev=0,65)
systemd   1 root  mem    REG   0,42          3077 /lib/x86_64-linux-gnu/libuuid.so.1.3.0 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2906 /lib/x86_64-linux-gnu/libblkid.so.1.1.0 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2934 /lib/x86_64-linux-gnu/libdl-2.23.so (path dev=0,65)
systemd   1 root  mem    REG   0,42          3024 /lib/x86_64-linux-gnu/libpcre.so.3.13.2 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2912 /lib/x86_64-linux-gnu/libc-2.23.so (path dev=0,65)
systemd   1 root  mem    REG   0,42          3039 /lib/x86_64-linux-gnu/libpthread-2.23.so (path dev=0,65)
systemd   1 root  mem    REG   0,42          2985 /lib/x86_64-linux-gnu/libmount.so.1.1.0 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2898 /lib/x86_64-linux-gnu/libapparmor.so.1.4.0 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2972 /lib/x86_64-linux-gnu/libkmod.so.2.3.0 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2904 /lib/x86_64-linux-gnu/libaudit.so.1.0.0 (path dev=0,65)
systemd   1 root  mem    REG   0,42          3013 /lib/x86_64-linux-gnu/libpam.so.0.83.1 (path dev=0,65)
systemd   1 root  mem    REG   0,42          3050 /lib/x86_64-linux-gnu/libseccomp.so.2.2.3 (path dev=0,65)
systemd   1 root  mem    REG   0,42          3047 /lib/x86_64-linux-gnu/librt-2.23.so (path dev=0,65)
systemd   1 root  mem    REG   0,42          2915 /lib/x86_64-linux-gnu/libcap.so.2.24 (path dev=0,65)
systemd   1 root  mem    REG   0,42          3051 /lib/x86_64-linux-gnu/libselinux.so.1 (path dev=0,65)
systemd   1 root  mem    REG   0,42          2888 /lib/x86_64-linux-gnu/ld-2.23.so (path dev=0,65)
systemd   1 root    0u   CHR    1,3      0t0 1030 /dev/null
systemd   1 root    1u   CHR    1,3      0t0 1030 /dev/null
systemd   1 root    2u   CHR    1,3      0t0 1030 /dev/null
root@close-grouse:~#