>>>> import os >>>> os.system("i=3") > 0 >>>> os.system("echo $i") > > 0 > > why i can not get the value of i?
Each call to os.system starts a new shell. Think about what would happen if you opened a terminal and typed: $ i=3 Then, close that terminal and open a new one. You would not be surprised that $ echo $i returns nothing. And, as mentioned by Andrew, even absent that problem os.system is not the way to obtain the data you are looking for. I realize this is now 5 days after you posted ... what were you ultimately attempting to accomplish? -- http://mail.python.org/mailman/listinfo/python-list