strcat() like in AWK language

str_var = "abc"
str_var = str_var "your new string"

Please refer to
http://www.unix.com/unix-for-dummies-questions-and-answers/12459-awk-question.html

re-direct the command line results to AWK's variable

Please refer to
http://wanggen.myweb.hinet.net/ach3/ach3.html?MywebPageId=2016271467005329861#getline