Sudden Problem with pexpect

[gw1500se]

I have a script the uses pexpect that has been working for years (common story, right?) that suddenly is failing. When I run the command manually I first get a prompt for 'Username'. When I run the pexpect script I get a trace back.

proc=pexpect.spawn('/usr/sbin/openvpn '+config)
proc.expect('Username:')

Output:
Traceback (most recent call last):
  File "/usr/local/bin/VPNsudo.py", line 89, in <module>
    proc=portOpen(configFile[useConfig])
  File "/usr/local/bin/VPNsudo.py", line 47, in portOpen
    proc.expect('Username:')
  File "/usr/lib/python2.7/site-packages/pexpect.py", line 1311, in expect
    return self.expect_list(compiled_pattern_list, timeout, searchwindowsize)
  File "/usr/lib/python2.7/site-packages/pexpect.py", line 1325, in expect_list
    return self.expect_loop(searcher_re(pattern_list), timeout, searchwindowsize)
  File "/usr/lib/python2.7/site-packages/pexpect.py", line 1396, in expect_loop
    raise EOF (str(e) + '\n' + str(self))
pexpect.EOF: End Of File (EOF) in read_nonblocking(). Exception style platform.
<pexpect.spawn object at 0x7f5d9121c7d0>
version: 2.3 ($Revision: 399 $)
command: /usr/sbin/openvpn
args: ['/usr/sbin/openvpn']
searcher: searcher_re:
    0: re.compile("Username:")
buffer (last 100 chars): 
before (last 100 chars): d *BEFORE* this.

General Standalone Options:
--show-gateway : Show info about default gateway.

after: <class 'pexpect.EOF'>
match: None
match_index: None
exitstatus: None
flag_eof: True
pid: 6653
child_fd: 4
closed: False
timeout: 30
delimiter: <class 'pexpect.EOF'>
logfile: None
logfile_read: None
logfile_send: None
maxread: 2000
ignorecase: False
searchwindowsize: None
delaybeforesend: 0.05
delayafterclose: 0.1
delayafterterminate: 0.1

One thing I noticed is that the username prompt is in bold. (not sure if it has always been that way) I don't think that would cause the problem but I though I'd mention it. If that somehow changed the string so it doesn't match I would expect a different error.

I could probably figure this out if I understood what this traceback was telling me. Can someone interpret it for me? TIA.

[bowlofred]

It was reading from the program trying to find your expected string. But then the program gave back an EOF (it exited). And the last few things that it received before exiting was:

d *BEFORE* this.

General Standalone Options:
--show-gateway : Show info about default gateway.

Do you recognize the output? Can your openvpn produce that output somehow?

I suspect that the stuff in config is making the command line invalid and it's just showing you the usage information rather than spawning.

[gw1500se]

Hmm. That is not what I get from manually launching. Thanks. At least you gave me a direction to look.

[bowlofred]

Hmm. That is not what I get from manually launching. Thanks. At least you gave me a direction to look.

What is the content of config?

Can you just see something happen with

import subprocess
...
print(subprocess.getoutput('/usr/sbin/openvpn '+config))