# List all kernel keys (parameters) and their values. sysctl [--all|-a] # As above, but show only specified keys and their values. sysctl [KEY_1 [KEY_2] ...] # As above, but instead output only the values. sysctl [--values|-n] [KEY_1 [KEY_2] ...] # Not nearly as useful, but alternatively, output only the key names. sysctl [--names|-N] [KEY_1 [KEY_2] ...] # Assign one or more kernel keys a new value; usually requires root access. sysctl [KEY_1=VALUE_1 [KEY_2=VALUE_2] ...]