Stuck in while True loop python

Question

I am stuck in a while True loop which I can't seem to break, any suggestions please:

command1 = transporterLink + " -m verify -f " + indir1 + " -u " + username + " -p " + password + " -o " + indir1 + "/VerifyLog.txt -s " + provider1 + " -v eXtreme"
master, slave = pty.openpty()
process = Popen(command1, shell=True, stdin=PIPE, stdout=slave, stderr=slave, close_fds=True)
stdout = os.fdopen(master)
while True:
 wx.Yield()
 line = stdout.readline()
 print line.rstrip()
 if not line:
 break
process.wait()

• NPE: Do you ever get an empty line from stdout?

Answer 1

The simplest explanation is that you never get an empty line from stdout. Note that print line.rstrip() does not modify line; for example, if the last line ended with a newline, the loop would continue.

• speedyrazor: Thanks NPE, any suggestions on how I could get out of this loop when at the end?
• SethMMorton: @speedyrazor You might consider if not line.strip(): instead.

Answer 2

Sorted. I know that at the end of the last line it will return one of two strings so just needed to search for either of these two:

process = Popen(command1, shell=True, stdin=PIPE, stdout=slave, stderr=slave, close_fds=True)
stdout = os.fdopen(master)
while True:
 wx.Yield()
 line = stdout.readline()
 line = line.rstrip()
 print line
 if "Returning 1" in line:
 break
 if "Returning 0" in line:
 break