One can look to /sys/class/net for all things network information wise:
z800:/# ls /sys/class/net enp1s0 enp2s0 lo z800:/# ls /sys/class/net/enp1s0 addr_assign_type address carrier dev_id device duplex gro_flush_timeout ifindex link_mode name_assign_type operstate phys_port_name power queues statistics tx_queue_len uevent addr_len broadcast carrier_changes dev_port dormant flags ifalias iflink mtu netdev_group phys_port_id phys_switch_id proto_down speed subsystem type z800:/# cat /sys/class/net/enp1s0/ifindex 3 z800:/# cat /sys/class/net/enp1s0/iflink 3 z800:/# cat /sys/class/net/enp1s0/operstate up z800:/# cat /sys/class/net/enp1s0/statistics/ collisions rx_compressed rx_errors rx_length_errors rx_packets tx_carrier_errors tx_errors tx_packets multicast rx_crc_errors rx_fifo_errors rx_missed_errors tx_aborted_errors tx_compressed tx_fifo_errors tx_window_errors rx_bytes rx_dropped rx_frame_errors rx_over_errors tx_bytes tx_dropped tx_heartbeat_errors z800:/# cat /sys/class/net/enp1s0/statistics/rx_bytes 26730983086 z800:/# cat /sys/class/net/enp1s0/speed 100 z800:/# cat /sys/class/net/enp1s0/mtu 1500