awk question (or sed, if that's better to use)

Shell Programming and Scripting
1

Hi all,

I'm pretty new to Unix (Sun) scripting, and wanted to try doing what many would probably believe is pretty easy. I tried searching the forums and only found bits and pieces of things I wanted to do below, but after many tries had a very hard time piecing it together.

Would anyone know how to:
a> Search the contents of "ifconfig -a" for either e1000 "or" igb0 and return only that "expression" (but not the whole word...ie: "e1000 instead of e1000g0" or "igb0 instead of igb0:1" )?

b&c> (I basically wanted to assign that 1-word result to $available_port) ...also needed, if neither "or" both are found, can $available_port = ERROR ?

extra info/clarification> There may be multiple times e1000 is found and that's okay. But if both e1000 "and" igb0 are found, that should instead assign ERROR to $available_port. Likewise, ERROR should be assigned if neither are found.

Thanks so much for your help,
CG

2 
available_port=`ifconfig -a | awk -vRS="\x00" '$0~/e1000/ && $0~/igb0/{print "ERROR";next} /e1000/{print "e1000";next} /igb0/{print "igb0";next} {print "ERROR"}'`

I know.. It's ugly.