System ID is the numerical identifier used in TAS license keys to
uniquely identify systems. The commands to determine this identifier
on the operating systems supported by TAS are as follows:
AIX : /bin/uname -m
HPUX : /bin/uname -i
IRIX : /sbin/sysinfo -s
Linux : use the MAC address of the first network interface (/sbin/ifconfig | grep HWaddr)
