Issue a single SNMP GETNEXT operation to a remote agent.
The command line options are per the snmpcmd options.
The remaining options are a list of OIDs to issue GETNEXTs for. GETNEXTs always find the next instance of data beyond the requested OID.
This requests the next object below the sysContact MIB node. This will result in returning the an instance of it (in the case of sysContact there is only one instance, the .0 instance):
# snmpgetnext -v 1 -c demopublic test.net-snmp.org sysContact SNMPv2-MIB::sysContact.0 = STRING: Net-SNMP Coders
If we take the resulting OID of what it gave us, we'll get the next one after this:
# snmpgetnext -v 1 -c demopublic test.net-snmp.org SNMPv2-MIB::sysContact.0 SNMPv2-MIB::sysName.0 = STRING: test.net-snmp.org
Issuing a whole bunch of GETNEXTs in a row is called "walking" and is exactly what the snmpwalk tool does.