Multiple expect in pexpect

Question

I am writing a code to automate testing using Pexpect So basically Telnet into a system and send commands. I have spawned a child for it. And I pass the child to function. Is it pass by reference or pass by value?

def test(child,clicommand,min,max,message):
    child.sendline("xyz")
    """Basically I am sending only sendline But I need 2 more expects. 
    Because of two execute called before this method.
    Both the expects are not blocking and the execute"""
    child.expect("() >")
    child.expect("() >")
    child.expect("() >")
    return


def execute(child,clicommand):
    print "Executing CLI command: "+clicommand
    child.sendline(clicommand)
    child.expect("() >")
    return


child = pexpect.spawn("telnet xx.xx.xx.xx xxxx")
child.sendline("")
child.expect("() >")
execute(child,"abc")
execute(child,"abc")
test(child,"xyz",1,2,"Error")

So are the expects being buffered or lined up? How Can I make it asynchronous? I even tried try except, but no exceptions are thrown

Answer 1

As stated here , you can't do asynchronous input/output with the same process, so a locking algorithm like this might work for you:

from threading import Lock  
lock=Lock()  

def send_command(str, int):           #int is the repetition number
    with lock:
        child.sendline(str)
        for x in range(int):
            child.expect("() >")

Then call it like this:

def test():
    send_command("xyz",3)

Hope it helps.