Merge lp:~stephane-duchesneau/ubuntu/trusty/pexpect/errno_handling_fix into lp:ubuntu/trusty/pexpect

[Stéphane Duchesneau]

This fixes a bug causing and unhandled exception within exception
handling. sys.exc_info()[1] was not treated correctly as a tuple
when a signal was sent (errno.EINTR)

[Barry Warsaw (barry)]

Hi Stéphane. First, thanks very much for your contribution to Ubuntu!

There's a bit of a problem with your merge proposal. As you'll see in the diff, it is including the .pc directory. This usually happens when the quilt patch stack for your branch is at a different level than the stack of the target branch. The fix for this when you're adding a new quilt patch, is to do one `quilt pop` so that the branch you're proposing for merge is at the same level as the branch you're proposing to merge into.

Aside from that, I'll note that the version of pexpect in Utopic (and Debian) is behind upstream's release on PyPI, and in fact this bug is fixed in the latest upstream release. Here's the upstream bug and diff:

http://pexpect.readthedocs.org/en/latest/history.html#releases

https://github.com/pexpect/pexpect/commit/a97f580d5cdd0f479ea64d36edc164ea769d4084 (this includes tests)

https://github.com/pexpect/pexpect/pull/38/

Since the package is team maintained in Debian, I will update it there, and that should automatically flow into Ubuntu 14.10. It's probably worth fixing this in Trusty though, so I'll file an SRU and attempt to backport the upstream fix into the Trusty branch.

[Stéphane Duchesneau (stephane-duchesneau)]

Hi, thank you for your extensive answer, I will work on my "quilt" skills and try to follow the SRU.

--
Stéphane Duchesneau
Savoir-faire Linux

----- Mail original -----

De: "Barry Warsaw" <email address hidden>
À: <email address hidden>
Envoyé: Jeudi 8 Mai 2014 15:50:12
Objet: Re: [Merge] lp:~stephane-duchesneau/ubuntu/trusty/pexpect/errno_handling_fix into lp:ubuntu/trusty/pexpect

Hi Stéphane. First, thanks very much for your contribution to Ubuntu!

There's a bit of a problem with your merge proposal. As you'll see in the diff, it is including the .pc directory. This usually happens when the quilt patch stack for your branch is at a different level than the stack of the target branch. The fix for this when you're adding a new quilt patch, is to do one `quilt pop` so that the branch you're proposing for merge is at the same level as the branch you're proposing to merge into.

Aside from that, I'll note that the version of pexpect in Utopic (and Debian) is behind upstream's release on PyPI, and in fact this bug is fixed in the latest upstream release. Here's the upstream bug and diff:

http://pexpect.readthedocs.org/en/latest/history.html#releases

https://github.com/pexpect/pexpect/commit/a97f580d5cdd0f479ea64d36edc164ea769d4084 (this includes tests)

https://github.com/pexpect/pexpect/pull/38/

Since the package is team maintained in Debian, I will update it there, and that should automatically flow into Ubuntu 14.10. It's probably worth fixing this in Trusty though, so I'll file an SRU and attempt to backport the upstream fix into the Trusty branch.
--
https://code.launchpad.net/~stephane-duchesneau/ubuntu/trusty/pexpect/errno_handling_fix/+merge/218813
You are the owner of lp:~stephane-duchesneau/ubuntu/trusty/pexpect/errno_handling_fix.

[Barry Warsaw (barry)]

LP: #1317600

Please subscribe to that bug and provide any additional information needed.

[Barry Warsaw (barry)]

Oops. It should be LP: #1317660

[Barry Warsaw (barry)]

I'm rejecting only because I fixed this in other ways as described above. Again, thanks for your contribution!

Unmerged revisions

10. By Stéphane Duchesneau on 2014-05-08

Add patch errno_handling_fix to fix interruption handling bug

=== modified file '.pc/applied-patches'
--- .pc/applied-patches	2013-12-06 20:20:26 +0000
+++ .pc/applied-patches	2014-05-08 13:59:49 +0000
@@ -0,0 +1,1 @@
+errno_handling_fix.patch

=== added directory '.pc/errno_handling_fix.patch'
=== added file '.pc/errno_handling_fix.patch/.timestamp'
=== added directory '.pc/errno_handling_fix.patch/pexpect'
=== added file '.pc/errno_handling_fix.patch/pexpect/__init__.py'
--- .pc/errno_handling_fix.patch/pexpect/__init__.py	1970-01-01 00:00:00 +0000
+++ .pc/errno_handling_fix.patch/pexpect/__init__.py	2014-05-08 13:59:49 +0000
@@ -0,0 +1,2051 @@
+'''Pexpect is a Python module for spawning child applications and controlling
+them automatically. Pexpect can be used for automating interactive applications
+such as ssh, ftp, passwd, telnet, etc. It can be used to a automate setup
+scripts for duplicating software package installations on different servers. It
+can be used for automated software testing. Pexpect is in the spirit of Don
+Libes' Expect, but Pexpect is pure Python. Other Expect-like modules for Python
+require TCL and Expect or require C extensions to be compiled. Pexpect does not
+use C, Expect, or TCL extensions. It should work on any platform that supports
+the standard Python pty module. The Pexpect interface focuses on ease of use so
+that simple tasks are easy.
+
+There are two main interfaces to the Pexpect system; these are the function,
+run() and the class, spawn. The spawn class is more powerful. The run()
+function is simpler than spawn, and is good for quickly calling program. When
+you call the run() function it executes a given program and then returns the
+output. This is a handy replacement for os.system().
+
+For example::
+
+    pexpect.run('ls -la')
+
+The spawn class is the more powerful interface to the Pexpect system. You can
+use this to spawn a child program then interact with it by sending input and
+expecting responses (waiting for patterns in the child's output).
+
+For example::
+
+    child = pexpect.spawn('scp foo [e-mail]:.')
+    child.expect('Password:')
+    child.sendline(mypassword)
+
+This works even for commands that ask for passwords or other input outside of
+the normal stdio streams. For example, ssh reads input directly from the TTY
+device which bypasses stdin.
+
+Credits: Noah Spurrier, Richard Holden, Marco Molteni, Kimberley Burchett,
+Robert Stone, Hartmut Goebel, Chad Schroeder, Erick Tryzelaar, Dave Kirby, Ids
+vander Molen, George Todd, Noel Taylor, Nicolas D. Cesar, Alexander Gattin,
+Jacques-Etienne Baudoux, Geoffrey Marshall, Francisco Lourenco, Glen Mabey,
+Karthik Gurusamy, Fernando Perez, Corey Minyard, Jon Cohen, Guillaume
+Chazarain, Andrew Ryan, Nick Craig-Wood, Andrew Stone, Jorgen Grahn, John
+Spiegel, Jan Grant, and Shane Kerr. Let me know if I forgot anyone.
+
+Pexpect is free, open source, and all that good stuff.
+http://pexpect.sourceforge.net/
+
+PEXPECT LICENSE
+
+    This license is approved by the OSI and FSF as GPL-compatible.
+        http://opensource.org/licenses/isc-license.txt
+
+    Copyright (c) 2012, Noah Spurrier <[e-mail]>
+    PERMISSION TO USE, COPY, MODIFY, AND/OR DISTRIBUTE THIS SOFTWARE FOR ANY
+    PURPOSE WITH OR WITHOUT FEE IS HEREBY GRANTED, PROVIDED THAT THE ABOVE
+    COPYRIGHT NOTICE AND THIS PERMISSION NOTICE APPEAR IN ALL COPIES.
+    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+    MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+'''
+
+try:
+    import os
+    import sys
+    import time
+    import select
+    import re
+    import struct
+    import resource
+    import types
+    import pty
+    import tty
+    import termios
+    import fcntl
+    import errno
+    import traceback
+    import signal
+    import codecs
+except ImportError:  # pragma: no cover
+    err = sys.exc_info()[1]
+    raise ImportError(str(err) + '''
+
+A critical module was not found. Probably this operating system does not
+support it. Pexpect is intended for UNIX-like operating systems.''')
+
+__version__ = '3.1'
+__revision__ = ''
+__all__ = ['ExceptionPexpect', 'EOF', 'TIMEOUT', 'spawn', 'spawnu', 'run', 'runu',
+           'which', 'split_command_line', '__version__', '__revision__']
+
+PY3 = (sys.version_info[0] >= 3)
+
+# Exception classes used by this module.
+class ExceptionPexpect(Exception):
+    '''Base class for all exceptions raised by this module.
+    '''
+
+    def __init__(self, value):
+        super(ExceptionPexpect, self).__init__(value)
+        self.value = value
+
+    def __str__(self):
+        return str(self.value)
+
+    def get_trace(self):
+        '''This returns an abbreviated stack trace with lines that only concern
+        the caller. In other words, the stack trace inside the Pexpect module
+        is not included. '''
+
+        tblist = traceback.extract_tb(sys.exc_info()[2])
+        tblist = [item for item in tblist if 'pexpect/__init__' not in item[0]]
+        tblist = traceback.format_list(tblist)
+        return ''.join(tblist)
+
+
+class EOF(ExceptionPexpect):
+    '''Raised when EOF is read from a child.
+    This usually means the child has exited.'''
+
+
+class TIMEOUT(ExceptionPexpect):
+    '''Raised when a read time exceeds the timeout. '''
+
+##class TIMEOUT_PATTERN(TIMEOUT):
+##    '''Raised when the pattern match time exceeds the timeout.
+##    This is different than a read TIMEOUT because the child process may
+##    give output, thus never give a TIMEOUT, but the output
+##    may never match a pattern.
+##    '''
+##class MAXBUFFER(ExceptionPexpect):
+##    '''Raised when a buffer fills before matching an expected pattern.'''
+
+
+def run(command, timeout=-1, withexitstatus=False, events=None,
+        extra_args=None, logfile=None, cwd=None, env=None):
+
+    '''
+    This function runs the given command; waits for it to finish; then
+    returns all output as a string. STDERR is included in output. If the full
+    path to the command is not given then the path is searched.
+
+    Note that lines are terminated by CR/LF (\\r\\n) combination even on
+    UNIX-like systems because this is the standard for pseudottys. If you set
+    'withexitstatus' to true, then run will return a tuple of (command_output,
+    exitstatus). If 'withexitstatus' is false then this returns just
+    command_output.
+
+    The run() function can often be used instead of creating a spawn instance.
+    For example, the following code uses spawn::
+
+        from pexpect import *
+        child = spawn('scp foo [e-mail]:.')
+        child.expect('(?i)password')
+        child.sendline(mypassword)
+
+    The previous code can be replace with the following::
+
+        from pexpect import *
+        run('scp foo [e-mail]:.', events={'(?i)password': mypassword})
+
+    **Examples**
+
+    Start the apache daemon on the local machine::
+
+        from pexpect import *
+        run("/usr/local/apache/bin/apachectl start")
+
+    Check in a file using SVN::
+
+        from pexpect import *
+        run("svn ci -m 'automatic commit' my_file.py")
+
+    Run a command and capture exit status::
+
+        from pexpect import *
+        (command_output, exitstatus) = run('ls -l /bin', withexitstatus=1)
+
+    The following will run SSH and execute 'ls -l' on the remote machine. The
+    password 'secret' will be sent if the '(?i)password' pattern is ever seen::
+
+        run("ssh [e-mail] 'ls -l'",
+            events={'(?i)password':'secret\\n'})
+
+    This will start mencoder to rip a video from DVD. This will also display
+    progress ticks every 5 seconds as it runs. For example::
+
+        from pexpect import *
+        def print_ticks(d):
+            print d['event_count'],
+        run("mencoder dvd://1 -o video.avi -oac copy -ovc copy",
+            events={TIMEOUT:print_ticks}, timeout=5)
+
+    The 'events' argument should be a dictionary of patterns and responses.
+    Whenever one of the patterns is seen in the command out run() will send the
+    associated response string. Note that you should put newlines in your
+    string if Enter is necessary. The responses may also contain callback
+    functions. Any callback is function that takes a dictionary as an argument.
+    The dictionary contains all the locals from the run() function, so you can
+    access the child spawn object or any other variable defined in run()
+    (event_count, child, and extra_args are the most useful). A callback may
+    return True to stop the current run process otherwise run() continues until
+    the next event. A callback may also return a string which will be sent to
+    the child. 'extra_args' is not used by directly run(). It provides a way to
+    pass data to a callback function through run() through the locals
+    dictionary passed to a callback.
+    '''
+    return _run(command, timeout=timeout, withexitstatus=withexitstatus,
+                events=events, extra_args=extra_args, logfile=logfile, cwd=cwd,
+                env=env, _spawn=spawn)
+
+def runu(command, timeout=-1, withexitstatus=False, events=None,
+        extra_args=None, logfile=None, cwd=None, env=None, **kwargs):
+    """This offers the same interface as :func:`run`, but using unicode.
+
+    Like :class:`spawnu`, you can pass ``encoding`` and ``errors`` parameters,
+    which will be used for both input and output.
+    """
+    return _run(command, timeout=timeout, withexitstatus=withexitstatus,
+                events=events, extra_args=extra_args, logfile=logfile, cwd=cwd,
+                env=env, _spawn=spawnu, **kwargs)
+
+def _run(command, timeout, withexitstatus, events, extra_args, logfile, cwd,
+         env, _spawn, **kwargs):
+    if timeout == -1:
+        child = _spawn(command, maxread=2000, logfile=logfile, cwd=cwd, env=env,
+                        **kwargs)
+    else:
+        child = _spawn(command, timeout=timeout, maxread=2000, logfile=logfile,
+                cwd=cwd, env=env, **kwargs)
+    if events is not None:
+        patterns = list(events.keys())
+        responses = list(events.values())
+    else:
+        # This assumes EOF or TIMEOUT will eventually cause run to terminate.
+        patterns = None
+        responses = None
+    child_result_list = []
+    event_count = 0
+    while True:
+        try:
+            index = child.expect(patterns)
+            if isinstance(child.after, child.allowed_string_types):
+                child_result_list.append(child.before + child.after)
+            else:
+                # child.after may have been a TIMEOUT or EOF,
+                # which we don't want appended to the list.
+                child_result_list.append(child.before)
+            if isinstance(responses[index], child.allowed_string_types):
+                child.send(responses[index])
+            elif isinstance(responses[index], types.FunctionType):
+                callback_result = responses[index](locals())
+                sys.stdout.flush()
+                if isinstance(callback_result, child.allowed_string_types):
+                    child.send(callback_result)
+                elif callback_result:
+                    break
+            else:
+                raise TypeError('The callback must be a string or function.')
+            event_count = event_count + 1
+        except TIMEOUT:
+            child_result_list.append(child.before)
+            break
+        except EOF:
+            child_result_list.append(child.before)
+            break
+    child_result = child.string_type().join(child_result_list)
+    if withexitstatus:
+        child.close()
+        return (child_result, child.exitstatus)
+    else:
+        return child_result
+
+class spawn(object):
+    '''This is the main class interface for Pexpect. Use this class to start
+    and control child applications. '''
+    string_type = bytes
+    if PY3:
+        allowed_string_types = (bytes, str)
+        @staticmethod
+        def _chr(c):
+            return bytes([c])
+        linesep = os.linesep.encode('ascii')
+
+        @staticmethod
+        def write_to_stdout(b):
+            try:
+                return sys.stdout.buffer.write(b)
+            except AttributeError:
+                # If stdout has been replaced, it may not have .buffer
+                return sys.stdout.write(b.decode('ascii', 'replace'))
+    else:
+        allowed_string_types = (basestring,)  # analysis:ignore
+        _chr = staticmethod(chr)
+        linesep = os.linesep
+        write_to_stdout = sys.stdout.write
+
+    encoding = None
+
+    def __init__(self, command, args=[], timeout=30, maxread=2000,
+        searchwindowsize=None, logfile=None, cwd=None, env=None,
+        ignore_sighup=True):
+
+        '''This is the constructor. The command parameter may be a string that
+        includes a command and any arguments to the command. For example::
+
+            child = pexpect.spawn('/usr/bin/ftp')
+            child = pexpect.spawn('/usr/bin/ssh [e-mail]')
+            child = pexpect.spawn('ls -latr /tmp')
+
+        You may also construct it with a list of arguments like so::
+
+            child = pexpect.spawn('/usr/bin/ftp', [])
+            child = pexpect.spawn('/usr/bin/ssh', ['[e-mail]'])
+            child = pexpect.spawn('ls', ['-latr', '/tmp'])
+
+        After this the child application will be created and will be ready to
+        talk to. For normal use, see expect() and send() and sendline().
+
+        Remember that Pexpect does NOT interpret shell meta characters such as
+        redirect, pipe, or wild cards (``>``, ``|``, or ``*``). This is a
+        common mistake.  If you want to run a command and pipe it through
+        another command then you must also start a shell. For example::
+
+            child = pexpect.spawn('/bin/bash -c "ls -l | grep LOG > logs.txt"')
+            child.expect(pexpect.EOF)
+
+        The second form of spawn (where you pass a list of arguments) is useful
+        in situations where you wish to spawn a command and pass it its own
+        argument list. This can make syntax more clear. For example, the
+        following is equivalent to the previous example::
+
+            shell_cmd = 'ls -l | grep LOG > logs.txt'
+            child = pexpect.spawn('/bin/bash', ['-c', shell_cmd])
+            child.expect(pexpect.EOF)
+
+        The maxread attribute sets the read buffer size. This is maximum number
+        of bytes that Pexpect will try to read from a TTY at one time. Setting
+        the maxread size to 1 will turn off buffering. Setting the maxread
+        value higher may help performance in cases where large amounts of
+        output are read back from the child. This feature is useful in
+        conjunction with searchwindowsize.
+
+        The searchwindowsize attribute sets the how far back in the incoming
+        seach buffer Pexpect will search for pattern matches. Every time
+        Pexpect reads some data from the child it will append the data to the
+        incoming buffer. The default is to search from the beginning of the
+        incoming buffer each time new data is read from the child. But this is
+        very inefficient if you are running a command that generates a large
+        amount of data where you want to match. The searchwindowsize does not
+        affect the size of the incoming data buffer. You will still have
+        access to the full buffer after expect() returns.
+
+        The logfile member turns on or off logging. All input and output will
+        be copied to the given file object. Set logfile to None to stop
+        logging. This is the default. Set logfile to sys.stdout to echo
+        everything to standard output. The logfile is flushed after each write.
+
+        Example log input and output to a file::
+
+            child = pexpect.spawn('some_command')
+            fout = file('mylog.txt','w')
+            child.logfile = fout
+
+        Example log to stdout::
+
+            child = pexpect.spawn('some_command')
+            child.logfile = sys.stdout
+
+        The logfile_read and logfile_send members can be used to separately log
+        the input from the child and output sent to the child. Sometimes you
+        don't want to see everything you write to the child. You only want to
+        log what the child sends back. For example::
+
+            child = pexpect.spawn('some_command')
+            child.logfile_read = sys.stdout
+
+        To separately log output sent to the child use logfile_send::
+
+            self.logfile_send = fout
+
+        If ``ignore_sighup`` is True, the child process will ignore SIGHUP
+        signals. For now, the default is True, to preserve the behaviour of
+        earlier versions of Pexpect, but you should pass this explicitly if you
+        want to rely on it.
+
+        The delaybeforesend helps overcome a weird behavior that many users
+        were experiencing. The typical problem was that a user would expect() a
+        "Password:" prompt and then immediately call sendline() to send the
+        password. The user would then see that their password was echoed back
+        to them. Passwords don't normally echo. The problem is caused by the
+        fact that most applications print out the "Password" prompt and then
+        turn off stdin echo, but if you send your password before the
+        application turned off echo, then you get your password echoed.
+        Normally this wouldn't be a problem when interacting with a human at a
+        real keyboard. If you introduce a slight delay just before writing then
+        this seems to clear up the problem. This was such a common problem for
+        many users that I decided that the default pexpect behavior should be
+        to sleep just before writing to the child application. 1/20th of a
+        second (50 ms) seems to be enough to clear up the problem. You can set
+        delaybeforesend to 0 to return to the old behavior. Most Linux machines
+        don't like this to be below 0.03. I don't know why.
+
+        Note that spawn is clever about finding commands on your path.
+        It uses the same logic that "which" uses to find executables.
+
+        If you wish to get the exit status of the child you must call the
+        close() method. The exit or signal status of the child will be stored
+        in self.exitstatus or self.signalstatus. If the child exited normally
+        then exitstatus will store the exit return code and signalstatus will
+        be None. If the child was terminated abnormally with a signal then
+        signalstatus will store the signal value and exitstatus will be None.
+        If you need more detail you can also read the self.status member which
+        stores the status returned by os.waitpid. You can interpret this using
+        os.WIFEXITED/os.WEXITSTATUS or os.WIFSIGNALED/os.TERMSIG. '''
+
+        self.STDIN_FILENO = pty.STDIN_FILENO
+        self.STDOUT_FILENO = pty.STDOUT_FILENO
+        self.STDERR_FILENO = pty.STDERR_FILENO
+        self.stdin = sys.stdin
+        self.stdout = sys.stdout
+        self.stderr = sys.stderr
+
+        self.searcher = None
+        self.ignorecase = False
+        self.before = None
+        self.after = None
+        self.match = None
+        self.match_index = None
+        self.terminated = True
+        self.exitstatus = None
+        self.signalstatus = None
+        # status returned by os.waitpid
+        self.status = None
+        self.flag_eof = False
+        self.pid = None
+        # the chile filedescriptor is initially closed
+        self.child_fd = -1
+        self.timeout = timeout
+        self.delimiter = EOF
+        self.logfile = logfile
+        # input from child (read_nonblocking)
+        self.logfile_read = None
+        # output to send (send, sendline)
+        self.logfile_send = None
+        # max bytes to read at one time into buffer
+        self.maxread = maxread
+        # This is the read buffer. See maxread.
+        self.buffer = self.string_type()
+        # Data before searchwindowsize point is preserved, but not searched.
+        self.searchwindowsize = searchwindowsize
+        # Delay used before sending data to child. Time in seconds.
+        # Most Linux machines don't like this to be below 0.03 (30 ms).
+        self.delaybeforesend = 0.05
+        # Used by close() to give kernel time to update process status.
+        # Time in seconds.
+        self.delayafterclose = 0.1
+        # Used by terminate() to give kernel time to update process status.
+        # Time in seconds.
+        self.delayafterterminate = 0.1
+        self.softspace = False
+        self.name = '<' + repr(self) + '>'
+        self.closed = True
+        self.cwd = cwd
+        self.env = env
+        self.ignore_sighup = ignore_sighup
+        # This flags if we are running on irix
+        self.__irix_hack = (sys.platform.lower().find('irix') >= 0)
+        # Solaris uses internal __fork_pty(). All others use pty.fork().
+        if ((sys.platform.lower().find('solaris') >= 0)
+            or (sys.platform.lower().find('sunos5') >= 0)):
+            self.use_native_pty_fork = False
+        else:
+            self.use_native_pty_fork = True
+
+        # Support subclasses that do not use command or args.
+        if command is None:
+            self.command = None
+            self.args = None
+            self.name = '<pexpect factory incomplete>'
+        else:
+            self._spawn(command, args)
+
+    @staticmethod
+    def _coerce_expect_string(s):
+        if not isinstance(s, bytes):
+            return s.encode('ascii')
+        return s
+
+    @staticmethod
+    def _coerce_send_string(s):
+        if not isinstance(s, bytes):
+            return s.encode('utf-8')
+        return s
+
+    @staticmethod
+    def _coerce_read_string(s):
+        return s
+
+    def __del__(self):
+        '''This makes sure that no system resources are left open. Python only
+        garbage collects Python objects. OS file descriptors are not Python
+        objects, so they must be handled explicitly. If the child file
+        descriptor was opened outside of this class (passed to the constructor)
+        then this does not close it. '''
+
+        if not self.closed:
+            # It is possible for __del__ methods to execute during the
+            # teardown of the Python VM itself. Thus self.close() may
+            # trigger an exception because os.close may be None.
+            try:
+                self.close()
+            # which exception, shouldnt' we catch explicitly .. ?
+            except:
+                pass
+
+    def __str__(self):
+        '''This returns a human-readable string that represents the state of
+        the object. '''
+
+        s = []
+        s.append(repr(self))
+        s.append('version: ' + __version__)
+        s.append('command: ' + str(self.command))
+        s.append('args: %r' % (self.args,))
+        s.append('searcher: %r' % (self.searcher,))
+        s.append('buffer (last 100 chars): %r' % (self.buffer)[-100:],)
+        s.append('before (last 100 chars): %r' % (self.before)[-100:],)
+        s.append('after: %r' % (self.after,))
+        s.append('match: %r' % (self.match,))
+        s.append('match_index: ' + str(self.match_index))
+        s.append('exitstatus: ' + str(self.exitstatus))
+        s.append('flag_eof: ' + str(self.flag_eof))
+        s.append('pid: ' + str(self.pid))
+        s.append('child_fd: ' + str(self.child_fd))
+        s.append('closed: ' + str(self.closed))
+        s.append('timeout: ' + str(self.timeout))
+        s.append('delimiter: ' + str(self.delimiter))
+        s.append('logfile: ' + str(self.logfile))
+        s.append('logfile_read: ' + str(self.logfile_read))
+        s.append('logfile_send: ' + str(self.logfile_send))
+        s.append('maxread: ' + str(self.maxread))
+        s.append('ignorecase: ' + str(self.ignorecase))
+        s.append('searchwindowsize: ' + str(self.searchwindowsize))
+        s.append('delaybeforesend: ' + str(self.delaybeforesend))
+        s.append('delayafterclose: ' + str(self.delayafterclose))
+        s.append('delayafterterminate: ' + str(self.delayafterterminate))
+        return '\n'.join(s)
+
+    def _spawn(self, command, args=[]):
+        '''This starts the given command in a child process. This does all the
+        fork/exec type of stuff for a pty. This is called by __init__. If args
+        is empty then command will be parsed (split on spaces) and args will be
+        set to parsed arguments. '''
+
+        # The pid and child_fd of this object get set by this method.
+        # Note that it is difficult for this method to fail.
+        # You cannot detect if the child process cannot start.
+        # So the only way you can tell if the child process started
+        # or not is to try to read from the file descriptor. If you get
+        # EOF immediately then it means that the child is already dead.
+        # That may not necessarily be bad because you may have spawned a child
+        # that performs some task; creates no stdout output; and then dies.
+
+        # If command is an int type then it may represent a file descriptor.
+        if isinstance(command, type(0)):
+            raise ExceptionPexpect('Command is an int type. ' +
+                    'If this is a file descriptor then maybe you want to ' +
+                    'use fdpexpect.fdspawn which takes an existing ' +
+                    'file descriptor instead of a command string.')
+
+        if not isinstance(args, type([])):
+            raise TypeError('The argument, args, must be a list.')
+
+        if args == []:
+            self.args = split_command_line(command)
+            self.command = self.args[0]
+        else:
+            # Make a shallow copy of the args list.
+            self.args = args[:]
+            self.args.insert(0, command)
+            self.command = command
+
+        command_with_path = which(self.command)
+        if command_with_path is None:
+            raise ExceptionPexpect('The command was not found or was not ' +
+                    'executable: %s.' % self.command)
+        self.command = command_with_path
+        self.args[0] = self.command
+
+        self.name = '<' + ' '.join(self.args) + '>'
+
+        assert self.pid is None, 'The pid member must be None.'
+        assert self.command is not None, 'The command member must not be None.'
+
+        if self.use_native_pty_fork:
+            try:
+                self.pid, self.child_fd = pty.fork()
+            except OSError:
+                err = sys.exc_info()[1]
+                raise ExceptionPexpect('pty.fork() failed: ' + str(err))
+        else:
+            # Use internal __fork_pty
+            self.pid, self.child_fd = self.__fork_pty()
+
+        if self.pid == 0:
+            # Child
+            try:
+                # used by setwinsize()
+                self.child_fd = sys.stdout.fileno()
+                self.setwinsize(24, 80)
+            # which exception, shouldnt' we catch explicitly .. ?
+            except:
+                # Some platforms do not like setwinsize (Cygwin).
+                # This will cause problem when running applications that
+                # are very picky about window size.
+                # This is a serious limitation, but not a show stopper.
+                pass
+            # Do not allow child to inherit open file descriptors from parent.
+            max_fd = resource.getrlimit(resource.RLIMIT_NOFILE)[0]
+            for i in range(3, max_fd):
+                try:
+                    os.close(i)
+                except OSError:
+                    pass
+
+            if self.ignore_sighup:
+                signal.signal(signal.SIGHUP, signal.SIG_IGN)
+
+            if self.cwd is not None:
+                os.chdir(self.cwd)
+            if self.env is None:
+                os.execv(self.command, self.args)
+            else:
+                os.execvpe(self.command, self.args, self.env)
+
+        # Parent
+        self.terminated = False
+        self.closed = False
+
+    def __fork_pty(self):
+        '''This implements a substitute for the forkpty system call. This
+        should be more portable than the pty.fork() function. Specifically,
+        this should work on Solaris.
+
+        Modified 10.06.05 by Geoff Marshall: Implemented __fork_pty() method to
+        resolve the issue with Python's pty.fork() not supporting Solaris,
+        particularly ssh. Based on patch to posixmodule.c authored by Noah
+        Spurrier::
+
+            http://mail.python.org/pipermail/python-dev/2003-May/035281.html
+
+        '''
+
+        parent_fd, child_fd = os.openpty()
+        if parent_fd < 0 or child_fd < 0:
+            raise ExceptionPexpect("Could not open with os.openpty().")
+
+        pid = os.fork()
+        if pid < 0:
+            raise ExceptionPexpect("Failed os.fork().")
+        elif pid == 0:
+            # Child.
+            os.close(parent_fd)
+            self.__pty_make_controlling_tty(child_fd)
+
+            os.dup2(child_fd, 0)
+            os.dup2(child_fd, 1)
+            os.dup2(child_fd, 2)
+
+            if child_fd > 2:
+                os.close(child_fd)
+        else:
+            # Parent.
+            os.close(child_fd)
+
+        return pid, parent_fd
+
+    def __pty_make_controlling_tty(self, tty_fd):
+        '''This makes the pseudo-terminal the controlling tty. This should be
+        more portable than the pty.fork() function. Specifically, this should
+        work on Solaris. '''
+
+        child_name = os.ttyname(tty_fd)
+
+        # Disconnect from controlling tty. Harmless if not already connected.
+        try:
+            fd = os.open("/dev/tty", os.O_RDWR | os.O_NOCTTY)
+            if fd >= 0:
+                os.close(fd)
+        # which exception, shouldnt' we catch explicitly .. ?
+        except:
+            # Already disconnected. This happens if running inside cron.
+            pass
+
+        os.setsid()
+
+        # Verify we are disconnected from controlling tty
+        # by attempting to open it again.
+        try:
+            fd = os.open("/dev/tty", os.O_RDWR | os.O_NOCTTY)
+            if fd >= 0:
+                os.close(fd)
+                raise ExceptionPexpect('Failed to disconnect from ' +
+                    'controlling tty. It is still possible to open /dev/tty.')
+        # which exception, shouldnt' we catch explicitly .. ?
+        except:
+            # Good! We are disconnected from a controlling tty.
+            pass
+
+        # Verify we can open child pty.
+        fd = os.open(child_name, os.O_RDWR)
+        if fd < 0:
+            raise ExceptionPexpect("Could not open child pty, " + child_name)
+        else:
+            os.close(fd)
+
+        # Verify we now have a controlling tty.
+        fd = os.open("/dev/tty", os.O_WRONLY)
+        if fd < 0:
+            raise ExceptionPexpect("Could not open controlling tty, /dev/tty")
+        else:
+            os.close(fd)
+
+    def fileno(self):
+        '''This returns the file descriptor of the pty for the child.
+        '''
+        return self.child_fd
+
+    def close(self, force=True):
+        '''This closes the connection with the child application. Note that
+        calling close() more than once is valid. This emulates standard Python
+        behavior with files. Set force to True if you want to make sure that
+        the child is terminated (SIGKILL is sent if the child ignores SIGHUP
+        and SIGINT). '''
+
+        if not self.closed:
+            self.flush()
+            os.close(self.child_fd)
+            # Give kernel time to update process status.
+            time.sleep(self.delayafterclose)
+            if self.isalive():
+                if not self.terminate(force):
+                    raise ExceptionPexpect('Could not terminate the child.')
+            self.child_fd = -1
+            self.closed = True
+            #self.pid = None
+
+    def flush(self):
+        '''This does nothing. It is here to support the interface for a
+        File-like object. '''
+
+        pass
+
+    def isatty(self):
+        '''This returns True if the file descriptor is open and connected to a
+        tty(-like) device, else False. '''
+
+        return os.isatty(self.child_fd)
+
+    def waitnoecho(self, timeout=-1):
+        '''This waits until the terminal ECHO flag is set False. This returns
+        True if the echo mode is off. This returns False if the ECHO flag was
+        not set False before the timeout. This can be used to detect when the
+        child is waiting for a password. Usually a child application will turn
+        off echo mode when it is waiting for the user to enter a password. For
+        example, instead of expecting the "password:" prompt you can wait for
+        the child to set ECHO off::
+
+            p = pexpect.spawn('ssh [e-mail]')
+            p.waitnoecho()
+            p.sendline(mypassword)
+
+        If timeout==-1 then this method will use the value in self.timeout.
+        If timeout==None then this method to block until ECHO flag is False.
+        '''
+
+        if timeout == -1:
+            timeout = self.timeout
+        if timeout is not None:
+            end_time = time.time() + timeout
+        while True:
+            if not self.getecho():
+                return True
+            if timeout < 0 and timeout is not None:
+                return False
+            if timeout is not None:
+                timeout = end_time - time.time()
+            time.sleep(0.1)
+
+    def getecho(self):
+        '''This returns the terminal echo mode. This returns True if echo is
+        on or False if echo is off. Child applications that are expecting you
+        to enter a password often set ECHO False. See waitnoecho(). '''
+
+        attr = termios.tcgetattr(self.child_fd)
+        if attr[3] & termios.ECHO:
+            return True
+        return False
+
+    def setecho(self, state):
+        '''This sets the terminal echo mode on or off. Note that anything the
+        child sent before the echo will be lost, so you should be sure that
+        your input buffer is empty before you call setecho(). For example, the
+        following will work as expected::
+
+            p = pexpect.spawn('cat') # Echo is on by default.
+            p.sendline('1234') # We expect see this twice from the child...
+            p.expect(['1234']) # ... once from the tty echo...
+            p.expect(['1234']) # ... and again from cat itself.
+            p.setecho(False) # Turn off tty echo
+            p.sendline('abcd') # We will set this only once (echoed by cat).
+            p.sendline('wxyz') # We will set this only once (echoed by cat)
+            p.expect(['abcd'])
+            p.expect(['wxyz'])
+
+        The following WILL NOT WORK because the lines sent before the setecho
+        will be lost::
+
+            p = pexpect.spawn('cat')
+            p.sendline('1234')
+            p.setecho(False) # Turn off tty echo
+            p.sendline('abcd') # We will set this only once (echoed by cat).
+            p.sendline('wxyz') # We will set this only once (echoed by cat)
+            p.expect(['1234'])
+            p.expect(['1234'])
+            p.expect(['abcd'])
+            p.expect(['wxyz'])
+        '''
+
+        self.child_fd
+        attr = termios.tcgetattr(self.child_fd)
+        if state:
+            attr[3] = attr[3] | termios.ECHO
+        else:
+            attr[3] = attr[3] & ~termios.ECHO
+        # I tried TCSADRAIN and TCSAFLUSH, but
+        # these were inconsistent and blocked on some platforms.
+        # TCSADRAIN would probably be ideal if it worked.
+        termios.tcsetattr(self.child_fd, termios.TCSANOW, attr)
+
+    def _log(self, s, direction):
+        if self.logfile is not None:
+            self.logfile.write(s)
+            self.logfile.flush()
+        second_log = self.logfile_send if (direction=='send') else self.logfile_read
+        if second_log is not None:
+            second_log.write(s)
+            second_log.flush()
+
+    def read_nonblocking(self, size=1, timeout=-1):
+        '''This reads at most size characters from the child application. It
+        includes a timeout. If the read does not complete within the timeout
+        period then a TIMEOUT exception is raised. If the end of file is read
+        then an EOF exception will be raised. If a log file was set using
+        setlog() then all data will also be written to the log file.
+
+        If timeout is None then the read may block indefinitely.
+        If timeout is -1 then the self.timeout value is used. If timeout is 0
+        then the child is polled and if there is no data immediately ready
+        then this will raise a TIMEOUT exception.
+
+        The timeout refers only to the amount of time to read at least one
+        character. This is not effected by the 'size' parameter, so if you call
+        read_nonblocking(size=100, timeout=30) and only one character is
+        available right away then one character will be returned immediately.
+        It will not wait for 30 seconds for another 99 characters to come in.
+
+        This is a wrapper around os.read(). It uses select.select() to
+        implement the timeout. '''
+
+        if self.closed:
+            raise ValueError('I/O operation on closed file.')
+
+        if timeout == -1:
+            timeout = self.timeout
+
+        # Note that some systems such as Solaris do not give an EOF when
+        # the child dies. In fact, you can still try to read
+        # from the child_fd -- it will block forever or until TIMEOUT.
+        # For this case, I test isalive() before doing any reading.
+        # If isalive() is false, then I pretend that this is the same as EOF.
+        if not self.isalive():
+            # timeout of 0 means "poll"
+            r, w, e = self.__select([self.child_fd], [], [], 0)
+            if not r:
+                self.flag_eof = True
+                raise EOF('End Of File (EOF). Braindead platform.')
+        elif self.__irix_hack:
+            # Irix takes a long time before it realizes a child was terminated.
+            # FIXME So does this mean Irix systems are forced to always have
+            # FIXME a 2 second delay when calling read_nonblocking? That sucks.
+            r, w, e = self.__select([self.child_fd], [], [], 2)
+            if not r and not self.isalive():
+                self.flag_eof = True
+                raise EOF('End Of File (EOF). Slow platform.')
+
+        r, w, e = self.__select([self.child_fd], [], [], timeout)
+
+        if not r:
+            if not self.isalive():
+                # Some platforms, such as Irix, will claim that their
+                # processes are alive; timeout on the select; and
+                # then finally admit that they are not alive.
+                self.flag_eof = True
+                raise EOF('End of File (EOF). Very slow platform.')
+            else:
+                raise TIMEOUT('Timeout exceeded.')
+
+        if self.child_fd in r:
+            try:
+                s = os.read(self.child_fd, size)
+            except OSError:
+                # Linux does this
+                self.flag_eof = True
+                raise EOF('End Of File (EOF). Exception style platform.')
+            if s == b'':
+                # BSD style
+                self.flag_eof = True
+                raise EOF('End Of File (EOF). Empty string style platform.')
+
+            s = self._coerce_read_string(s)
+            self._log(s, 'read')
+            return s
+
+        raise ExceptionPexpect('Reached an unexpected state.')
+
+    def read(self, size=-1):
+        '''This reads at most "size" bytes from the file (less if the read hits
+        EOF before obtaining size bytes). If the size argument is negative or
+        omitted, read all data until EOF is reached. The bytes are returned as
+        a string object. An empty string is returned when EOF is encountered
+        immediately. '''
+
+        if size == 0:
+            return self.string_type()
+        if size < 0:
+            # delimiter default is EOF
+            self.expect(self.delimiter)
+            return self.before
+
+        # I could have done this more directly by not using expect(), but
+        # I deliberately decided to couple read() to expect() so that
+        # I would catch any bugs early and ensure consistant behavior.
+        # It's a little less efficient, but there is less for me to
+        # worry about if I have to later modify read() or expect().
+        # Note, it's OK if size==-1 in the regex. That just means it
+        # will never match anything in which case we stop only on EOF.
+        cre = re.compile(self._coerce_expect_string('.{%d}' % size), re.DOTALL)
+        # delimiter default is EOF
+        index = self.expect([cre, self.delimiter])
+        if index == 0:
+            ### FIXME self.before should be ''. Should I assert this?
+            return self.after
+        return self.before
+
+    def readline(self, size=-1):
+        '''This reads and returns one entire line. The newline at the end of
+        line is returned as part of the string, unless the file ends without a
+        newline. An empty string is returned if EOF is encountered immediately.
+        This looks for a newline as a CR/LF pair (\\r\\n) even on UNIX because
+        this is what the pseudotty device returns. So contrary to what you may
+        expect you will receive newlines as \\r\\n.
+
+        If the size argument is 0 then an empty string is returned. In all
+        other cases the size argument is ignored, which is not standard
+        behavior for a file-like object. '''
+
+        if size == 0:
+            return self.string_type()
+        # delimiter default is EOF
+        index = self.expect([b'\r\n', self.delimiter])
+        if index == 0:
+            return self.before + b'\r\n'
+        else:
+            return self.before
+
+    def __iter__(self):
+        '''This is to support iterators over a file-like object.
+        '''
+        return iter(self.readline, self.string_type())
+
+    def readlines(self, sizehint=-1):
+        '''This reads until EOF using readline() and returns a list containing
+        the lines thus read. The optional 'sizehint' argument is ignored.
+        Remember, because this reads until EOF that means the child
+        process should have closed its stdout. If you run this method on
+        a child that is still running with its stdout open then this
+        method will block until it timesout.'''
+
+        lines = []
+        while True:
+            line = self.readline()
+            if not line:
+                break
+            lines.append(line)
+        return lines
+
+    def write(self, s):
+        '''This is similar to send() except that there is no return value.
+        '''
+
+        self.send(s)
+
+    def writelines(self, sequence):
+        '''This calls write() for each element in the sequence. The sequence
+        can be any iterable object producing strings, typically a list of
+        strings. This does not add line separators. There is no return value.
+        '''
+
+        for s in sequence:
+            self.write(s)
+
+    def send(self, s):
+        '''Sends string ``s`` to the child process, returning the number of
+        bytes written. If a logfile is specified, a copy is written to that
+        log. '''
+
+        time.sleep(self.delaybeforesend)
+
+        s = self._coerce_send_string(s)
+        self._log(s, 'send')
+
+        return self._send(s)
+
+    def _send(self, s):
+        return os.write(self.child_fd, s)
+
+    def sendline(self, s=''):
+        '''Wraps send(), sending string ``s`` to child process, with os.linesep
+        automatically appended. Returns number of bytes written. '''
+
+        n = self.send(s)
+        n = n + self.send(self.linesep)
+        return n
+
+    def sendcontrol(self, char):
+
+        '''Helper method that wraps send() with mnemonic access for sending control
+        character to the child (such as Ctrl-C or Ctrl-D).  For example, to send
+        Ctrl-G (ASCII 7, bell, '\a')::
+
+            child.sendcontrol('g')
+
+        See also, sendintr() and sendeof().
+        '''
+
+        char = char.lower()
+        a = ord(char)
+        if a >= 97 and a <= 122:
+            a = a - ord('a') + 1
+            return self.send(self._chr(a))
+        d = {'@': 0, '`': 0,
+            '[': 27, '{': 27,
+            '\\': 28, '|': 28,
+            ']': 29, '}': 29,
+            '^': 30, '~': 30,
+            '_': 31,
+            '?': 127}
+        if char not in d:
+            return 0
+        return self.send(self._chr(d[char]))
+
+    def sendeof(self):
+
+        '''This sends an EOF to the child. This sends a character which causes
+        the pending parent output buffer to be sent to the waiting child
+        program without waiting for end-of-line. If it is the first character
+        of the line, the read() in the user program returns 0, which signifies
+        end-of-file. This means to work as expected a sendeof() has to be
+        called at the beginning of a line. This method does not send a newline.
+        It is the responsibility of the caller to ensure the eof is sent at the
+        beginning of a line. '''
+
+        ### Hmmm... how do I send an EOF?
+        ###C  if ((m = write(pty, *buf, p - *buf)) < 0)
+        ###C      return (errno == EWOULDBLOCK) ? n : -1;
+        #fd = sys.stdin.fileno()
+        #old = termios.tcgetattr(fd) # remember current state
+        #attr = termios.tcgetattr(fd)
+        #attr[3] = attr[3] | termios.ICANON # ICANON must be set to see EOF
+        #try: # use try/finally to ensure state gets restored
+        #    termios.tcsetattr(fd, termios.TCSADRAIN, attr)
+        #    if hasattr(termios, 'CEOF'):
+        #        os.write(self.child_fd, '%c' % termios.CEOF)
+        #    else:
+        #        # Silly platform does not define CEOF so assume CTRL-D
+        #        os.write(self.child_fd, '%c' % 4)
+        #finally: # restore state
+        #    termios.tcsetattr(fd, termios.TCSADRAIN, old)
+        if hasattr(termios, 'VEOF'):
+            char = ord(termios.tcgetattr(self.child_fd)[6][termios.VEOF])
+        else:
+            # platform does not define VEOF so assume CTRL-D
+            char = 4
+        self.send(self._chr(char))
+
+    def sendintr(self):
+
+        '''This sends a SIGINT to the child. It does not require
+        the SIGINT to be the first character on a line. '''
+
+        if hasattr(termios, 'VINTR'):
+            char = ord(termios.tcgetattr(self.child_fd)[6][termios.VINTR])
+        else:
+            # platform does not define VINTR so assume CTRL-C
+            char = 3
+        self.send(self._chr(char))
+
+    def eof(self):
+
+        '''This returns True if the EOF exception was ever raised.
+        '''
+
+        return self.flag_eof
+
+    def terminate(self, force=False):
+
+        '''This forces a child process to terminate. It starts nicely with
+        SIGHUP and SIGINT. If "force" is True then moves onto SIGKILL. This
+        returns True if the child was terminated. This returns False if the
+        child could not be terminated. '''
+
+        if not self.isalive():
+            return True
+        try:
+            self.kill(signal.SIGHUP)
+            time.sleep(self.delayafterterminate)
+            if not self.isalive():
+                return True
+            self.kill(signal.SIGCONT)
+            time.sleep(self.delayafterterminate)
+            if not self.isalive():
+                return True
+            self.kill(signal.SIGINT)
+            time.sleep(self.delayafterterminate)
+            if not self.isalive():
+                return True
+            if force:
+                self.kill(signal.SIGKILL)
+                time.sleep(self.delayafterterminate)
+                if not self.isalive():
+                    return True
+                else:
+                    return False
+            return False
+        except OSError:
+            # I think there are kernel timing issues that sometimes cause
+            # this to happen. I think isalive() reports True, but the
+            # process is dead to the kernel.
+            # Make one last attempt to see if the kernel is up to date.
+            time.sleep(self.delayafterterminate)
+            if not self.isalive():
+                return True
+            else:
+                return False
+
+    def wait(self):
+
+        '''This waits until the child exits. This is a blocking call. This will
+        not read any data from the child, so this will block forever if the
+        child has unread output and has terminated. In other words, the child
+        may have printed output then called exit(), but, the child is
+        technically still alive until its output is read by the parent. '''
+
+        if self.isalive():
+            pid, status = os.waitpid(self.pid, 0)
+        else:
+            raise ExceptionPexpect('Cannot wait for dead child process.')
+        self.exitstatus = os.WEXITSTATUS(status)
+        if os.WIFEXITED(status):
+            self.status = status
+            self.exitstatus = os.WEXITSTATUS(status)
+            self.signalstatus = None
+            self.terminated = True
+        elif os.WIFSIGNALED(status):
+            self.status = status
+            self.exitstatus = None
+            self.signalstatus = os.WTERMSIG(status)
+            self.terminated = True
+        elif os.WIFSTOPPED(status):
+            # You can't call wait() on a child process in the stopped state.
+            raise ExceptionPexpect('Called wait() on a stopped child ' +
+                    'process. This is not supported. Is some other ' +
+                    'process attempting job control with our child pid?')
+        return self.exitstatus
+
+    def isalive(self):
+
+        '''This tests if the child process is running or not. This is
+        non-blocking. If the child was terminated then this will read the
+        exitstatus or signalstatus of the child. This returns True if the child
+        process appears to be running or False if not. It can take literally
+        SECONDS for Solaris to return the right status. '''
+
+        if self.terminated:
+            return False
+
+        if self.flag_eof:
+            # This is for Linux, which requires the blocking form
+            # of waitpid to # get status of a defunct process.
+            # This is super-lame. The flag_eof would have been set
+            # in read_nonblocking(), so this should be safe.
+            waitpid_options = 0
+        else:
+            waitpid_options = os.WNOHANG
+
+        try:
+            pid, status = os.waitpid(self.pid, waitpid_options)
+        except OSError:
+            err = sys.exc_info()[1]
+            # No child processes
+            if err.errno == errno.ECHILD:
+                raise ExceptionPexpect('isalive() encountered condition ' +
+                        'where "terminated" is 0, but there was no child ' +
+                        'process. Did someone else call waitpid() ' +
+                        'on our process?')
+            else:
+                raise err
+
+        # I have to do this twice for Solaris.
+        # I can't even believe that I figured this out...
+        # If waitpid() returns 0 it means that no child process
+        # wishes to report, and the value of status is undefined.
+        if pid == 0:
+            try:
+                ### os.WNOHANG) # Solaris!
+                pid, status = os.waitpid(self.pid, waitpid_options)
+            except OSError as e:
+                # This should never happen...
+                if e.errno == errno.ECHILD:
+                    raise ExceptionPexpect('isalive() encountered condition ' +
+                            'that should never happen. There was no child ' +
+                            'process. Did someone else call waitpid() ' +
+                            'on our process?')
+                else:
+                    raise
+
+            # If pid is still 0 after two calls to waitpid() then the process
+            # really is alive. This seems to work on all platforms, except for
+            # Irix which seems to require a blocking call on waitpid or select,
+            # so I let read_nonblocking take care of this situation
+            # (unfortunately, this requires waiting through the timeout).
+            if pid == 0:
+                return True
+
+        if pid == 0:
+            return True
+
+        if os.WIFEXITED(status):
+            self.status = status
+            self.exitstatus = os.WEXITSTATUS(status)
+            self.signalstatus = None
+            self.terminated = True
+        elif os.WIFSIGNALED(status):
+            self.status = status
+            self.exitstatus = None
+            self.signalstatus = os.WTERMSIG(status)
+            self.terminated = True
+        elif os.WIFSTOPPED(status):
+            raise ExceptionPexpect('isalive() encountered condition ' +
+                    'where child process is stopped. This is not ' +
+                    'supported. Is some other process attempting ' +
+                    'job control with our child pid?')
+        return False
+
+    def kill(self, sig):
+
+        '''This sends the given signal to the child application. In keeping
+        with UNIX tradition it has a misleading name. It does not necessarily
+        kill the child unless you send the right signal. '''
+
+        # Same as os.kill, but the pid is given for you.
+        if self.isalive():
+            os.kill(self.pid, sig)
+
+    def _pattern_type_err(self, pattern):
+        raise TypeError('got {badtype} ({badobj!r}) as pattern, must be one'
+                        ' of: {goodtypes}, pexpect.EOF, pexpect.TIMEOUT'\
+                        .format(badtype=type(pattern),
+                                badobj=pattern,
+                                goodtypes=', '.join([str(ast)\
+                                    for ast in self.allowed_string_types])
+                                )
+                        )
+
+    def compile_pattern_list(self, patterns):
+
+        '''This compiles a pattern-string or a list of pattern-strings.
+        Patterns must be a StringType, EOF, TIMEOUT, SRE_Pattern, or a list of
+        those. Patterns may also be None which results in an empty list (you
+        might do this if waiting for an EOF or TIMEOUT condition without
+        expecting any pattern).
+
+        This is used by expect() when calling expect_list(). Thus expect() is
+        nothing more than::
+
+             cpl = self.compile_pattern_list(pl)
+             return self.expect_list(cpl, timeout)
+
+        If you are using expect() within a loop it may be more
+        efficient to compile the patterns first and then call expect_list().
+        This avoid calls in a loop to compile_pattern_list()::
+
+             cpl = self.compile_pattern_list(my_pattern)
+             while some_condition:
+                ...
+                i = self.expect_list(clp, timeout)
+                ...
+        '''
+
+        if patterns is None:
+            return []
+        if not isinstance(patterns, list):
+            patterns = [patterns]
+
+        # Allow dot to match \n
+        compile_flags = re.DOTALL
+        if self.ignorecase:
+            compile_flags = compile_flags | re.IGNORECASE
+        compiled_pattern_list = []
+        for idx, p in enumerate(patterns):
+            if isinstance(p, self.allowed_string_types):
+                p = self._coerce_expect_string(p)
+                compiled_pattern_list.append(re.compile(p, compile_flags))
+            elif p is EOF:
+                compiled_pattern_list.append(EOF)
+            elif p is TIMEOUT:
+                compiled_pattern_list.append(TIMEOUT)
+            elif isinstance(p, type(re.compile(''))):
+                compiled_pattern_list.append(p)
+            else:
+                self._pattern_type_err(p)
+        return compiled_pattern_list
+
+    def expect(self, pattern, timeout=-1, searchwindowsize=-1):
+
+        '''This seeks through the stream until a pattern is matched. The
+        pattern is overloaded and may take several types. The pattern can be a
+        StringType, EOF, a compiled re, or a list of any of those types.
+        Strings will be compiled to re types. This returns the index into the
+        pattern list. If the pattern was not a list this returns index 0 on a
+        successful match. This may raise exceptions for EOF or TIMEOUT. To
+        avoid the EOF or TIMEOUT exceptions add EOF or TIMEOUT to the pattern
+        list. That will cause expect to match an EOF or TIMEOUT condition
+        instead of raising an exception.
+
+        If you pass a list of patterns and more than one matches, the first
+        match in the stream is chosen. If more than one pattern matches at that
+        point, the leftmost in the pattern list is chosen. For example::
+
+            # the input is 'foobar'
+            index = p.expect(['bar', 'foo', 'foobar'])
+            # returns 1('foo') even though 'foobar' is a "better" match
+
+        Please note, however, that buffering can affect this behavior, since
+        input arrives in unpredictable chunks. For example::
+
+            # the input is 'foobar'
+            index = p.expect(['foobar', 'foo'])
+            # returns 0('foobar') if all input is available at once,
+            # but returs 1('foo') if parts of the final 'bar' arrive late
+
+        After a match is found the instance attributes 'before', 'after' and
+        'match' will be set. You can see all the data read before the match in
+        'before'. You can see the data that was matched in 'after'. The
+        re.MatchObject used in the re match will be in 'match'. If an error
+        occurred then 'before' will be set to all the data read so far and
+        'after' and 'match' will be None.
+
+        If timeout is -1 then timeout will be set to the self.timeout value.
+
+        A list entry may be EOF or TIMEOUT instead of a string. This will
+        catch these exceptions and return the index of the list entry instead
+        of raising the exception. The attribute 'after' will be set to the
+        exception type. The attribute 'match' will be None. This allows you to
+        write code like this::
+
+                index = p.expect(['good', 'bad', pexpect.EOF, pexpect.TIMEOUT])
+                if index == 0:
+                    do_something()
+                elif index == 1:
+                    do_something_else()
+                elif index == 2:
+                    do_some_other_thing()
+                elif index == 3:
+                    do_something_completely_different()
+
+        instead of code like this::
+
+                try:
+                    index = p.expect(['good', 'bad'])
+                    if index == 0:
+                        do_something()
+                    elif index == 1:
+                        do_something_else()
+                except EOF:
+                    do_some_other_thing()
+                except TIMEOUT:
+                    do_something_completely_different()
+
+        These two forms are equivalent. It all depends on what you want. You
+        can also just expect the EOF if you are waiting for all output of a
+        child to finish. For example::
+
+                p = pexpect.spawn('/bin/ls')
+                p.expect(pexpect.EOF)
+                print p.before
+
+        If you are trying to optimize for speed then see expect_list().
+        '''
+
+        compiled_pattern_list = self.compile_pattern_list(pattern)
+        return self.expect_list(compiled_pattern_list,
+                timeout, searchwindowsize)
+
+    def expect_list(self, pattern_list, timeout=-1, searchwindowsize=-1):
+
+        '''This takes a list of compiled regular expressions and returns the
+        index into the pattern_list that matched the child output. The list may
+        also contain EOF or TIMEOUT(which are not compiled regular
+        expressions). This method is similar to the expect() method except that
+        expect_list() does not recompile the pattern list on every call. This
+        may help if you are trying to optimize for speed, otherwise just use
+        the expect() method.  This is called by expect(). If timeout==-1 then
+        the self.timeout value is used. If searchwindowsize==-1 then the
+        self.searchwindowsize value is used. '''
+
+        return self.expect_loop(searcher_re(pattern_list),
+                timeout, searchwindowsize)
+
+    def expect_exact(self, pattern_list, timeout=-1, searchwindowsize=-1):
+
+        '''This is similar to expect(), but uses plain string matching instead
+        of compiled regular expressions in 'pattern_list'. The 'pattern_list'
+        may be a string; a list or other sequence of strings; or TIMEOUT and
+        EOF.
+
+        This call might be faster than expect() for two reasons: string
+        searching is faster than RE matching and it is possible to limit the
+        search to just the end of the input buffer.
+
+        This method is also useful when you don't want to have to worry about
+        escaping regular expression characters that you want to match.'''
+
+        if (isinstance(pattern_list, self.allowed_string_types) or
+                pattern_list in (TIMEOUT, EOF)):
+            pattern_list = [pattern_list]
+
+        def prepare_pattern(pattern):
+            if pattern in (TIMEOUT, EOF):
+                return pattern
+            if isinstance(pattern, self.allowed_string_types):
+                return self._coerce_expect_string(pattern)
+            self._pattern_type_err(pattern)
+
+        try:
+            pattern_list = iter(pattern_list)
+        except TypeError:
+            self._pattern_type_err(pattern_list)
+        pattern_list = [prepare_pattern(p) for p in pattern_list]
+        return self.expect_loop(searcher_string(pattern_list),
+                timeout, searchwindowsize)
+
+    def expect_loop(self, searcher, timeout=-1, searchwindowsize=-1):
+
+        '''This is the common loop used inside expect. The 'searcher' should be
+        an instance of searcher_re or searcher_string, which describes how and
+        what to search for in the input.
+
+        See expect() for other arguments, return value and exceptions. '''
+
+        self.searcher = searcher
+
+        if timeout == -1:
+            timeout = self.timeout
+        if timeout is not None:
+            end_time = time.time() + timeout
+        if searchwindowsize == -1:
+            searchwindowsize = self.searchwindowsize
+
+        try:
+            incoming = self.buffer
+            freshlen = len(incoming)
+            while True:
+                # Keep reading until exception or return.
+                index = searcher.search(incoming, freshlen, searchwindowsize)
+                if index >= 0:
+                    self.buffer = incoming[searcher.end:]
+                    self.before = incoming[: searcher.start]
+                    self.after = incoming[searcher.start: searcher.end]
+                    self.match = searcher.match
+                    self.match_index = index
+                    return self.match_index
+                # No match at this point
+                if (timeout is not None) and (timeout < 0):
+                    raise TIMEOUT('Timeout exceeded in expect_any().')
+                # Still have time left, so read more data
+                c = self.read_nonblocking(self.maxread, timeout)
+                freshlen = len(c)
+                time.sleep(0.0001)
+                incoming = incoming + c
+                if timeout is not None:
+                    timeout = end_time - time.time()
+        except EOF:
+            err = sys.exc_info()[1]
+            self.buffer = self.string_type()
+            self.before = incoming
+            self.after = EOF
+            index = searcher.eof_index
+            if index >= 0:
+                self.match = EOF
+                self.match_index = index
+                return self.match_index
+            else:
+                self.match = None
+                self.match_index = None
+                raise EOF(str(err) + '\n' + str(self))
+        except TIMEOUT:
+            err = sys.exc_info()[1]
+            self.buffer = incoming
+            self.before = incoming
+            self.after = TIMEOUT
+            index = searcher.timeout_index
+            if index >= 0:
+                self.match = TIMEOUT
+                self.match_index = index
+                return self.match_index
+            else:
+                self.match = None
+                self.match_index = None
+                raise TIMEOUT(str(err) + '\n' + str(self))
+        except:
+            self.before = incoming
+            self.after = None
+            self.match = None
+            self.match_index = None
+            raise
+
+    def getwinsize(self):
+
+        '''This returns the terminal window size of the child tty. The return
+        value is a tuple of (rows, cols). '''
+
+        TIOCGWINSZ = getattr(termios, 'TIOCGWINSZ', 1074295912)
+        s = struct.pack('HHHH', 0, 0, 0, 0)
+        x = fcntl.ioctl(self.child_fd, TIOCGWINSZ, s)
+        return struct.unpack('HHHH', x)[0:2]
+
+    def setwinsize(self, rows, cols):
+
+        '''This sets the terminal window size of the child tty. This will cause
+        a SIGWINCH signal to be sent to the child. This does not change the
+        physical window size. It changes the size reported to TTY-aware
+        applications like vi or curses -- applications that respond to the
+        SIGWINCH signal. '''
+
+        # Check for buggy platforms. Some Python versions on some platforms
+        # (notably OSF1 Alpha and RedHat 7.1) truncate the value for
+        # termios.TIOCSWINSZ. It is not clear why this happens.
+        # These platforms don't seem to handle the signed int very well;
+        # yet other platforms like OpenBSD have a large negative value for
+        # TIOCSWINSZ and they don't have a truncate problem.
+        # Newer versions of Linux have totally different values for TIOCSWINSZ.
+        # Note that this fix is a hack.
+        TIOCSWINSZ = getattr(termios, 'TIOCSWINSZ', -2146929561)
+        if TIOCSWINSZ == 2148037735:
+            # Same bits, but with sign.
+            TIOCSWINSZ = -2146929561
+        # Note, assume ws_xpixel and ws_ypixel are zero.
+        s = struct.pack('HHHH', rows, cols, 0, 0)
+        fcntl.ioctl(self.fileno(), TIOCSWINSZ, s)
+
+    def interact(self, escape_character=chr(29),
+            input_filter=None, output_filter=None):
+
+        '''This gives control of the child process to the interactive user (the
+        human at the keyboard). Keystrokes are sent to the child process, and
+        the stdout and stderr output of the child process is printed. This
+        simply echos the child stdout and child stderr to the real stdout and
+        it echos the real stdin to the child stdin. When the user types the
+        escape_character this method will stop. The default for
+        escape_character is ^]. This should not be confused with ASCII 27 --
+        the ESC character. ASCII 29 was chosen for historical merit because
+        this is the character used by 'telnet' as the escape character. The
+        escape_character will not be sent to the child process.
+
+        You may pass in optional input and output filter functions. These
+        functions should take a string and return a string. The output_filter
+        will be passed all the output from the child process. The input_filter
+        will be passed all the keyboard input from the user. The input_filter
+        is run BEFORE the check for the escape_character.
+
+        Note that if you change the window size of the parent the SIGWINCH
+        signal will not be passed through to the child. If you want the child
+        window size to change when the parent's window size changes then do
+        something like the following example::
+
+            import pexpect, struct, fcntl, termios, signal, sys
+            def sigwinch_passthrough (sig, data):
+                s = struct.pack("HHHH", 0, 0, 0, 0)
+                a = struct.unpack('hhhh', fcntl.ioctl(sys.stdout.fileno(),
+                    termios.TIOCGWINSZ , s))
+                global p
+                p.setwinsize(a[0],a[1])
+            # Note this 'p' global and used in sigwinch_passthrough.
+            p = pexpect.spawn('/bin/bash')
+            signal.signal(signal.SIGWINCH, sigwinch_passthrough)
+            p.interact()
+        '''
+
+        # Flush the buffer.
+        self.write_to_stdout(self.buffer)
+        self.stdout.flush()
+        self.buffer = self.string_type()
+        mode = tty.tcgetattr(self.STDIN_FILENO)
+        tty.setraw(self.STDIN_FILENO)
+        if PY3:
+            escape_character = escape_character.encode('latin-1')
+        try:
+            self.__interact_copy(escape_character, input_filter, output_filter)
+        finally:
+            tty.tcsetattr(self.STDIN_FILENO, tty.TCSAFLUSH, mode)
+
+    def __interact_writen(self, fd, data):
+        '''This is used by the interact() method.
+        '''
+
+        while data != b'' and self.isalive():
+            n = os.write(fd, data)
+            data = data[n:]
+
+    def __interact_read(self, fd):
+        '''This is used by the interact() method.
+        '''
+
+        return os.read(fd, 1000)
+
+    def __interact_copy(self, escape_character=None,
+            input_filter=None, output_filter=None):
+
+        '''This is used by the interact() method.
+        '''
+
+        while self.isalive():
+            r, w, e = self.__select([self.child_fd, self.STDIN_FILENO], [], [])
+            if self.child_fd in r:
+                try:
+                    data = self.__interact_read(self.child_fd)
+                except OSError as e:
+                    # The subprocess may have closed before we get to reading it
+                    if e.errno != errno.EIO:
+                        raise
+                if output_filter:
+                    data = output_filter(data)
+                if self.logfile is not None:
+                    self.logfile.write(data)
+                    self.logfile.flush()
+                os.write(self.STDOUT_FILENO, data)
+            if self.STDIN_FILENO in r:
+                data = self.__interact_read(self.STDIN_FILENO)
+                if input_filter:
+                    data = input_filter(data)
+                i = data.rfind(escape_character)
+                if i != -1:
+                    data = data[:i]
+                    self.__interact_writen(self.child_fd, data)
+                    break
+                self.__interact_writen(self.child_fd, data)
+
+    def __select(self, iwtd, owtd, ewtd, timeout=None):
+
+        '''This is a wrapper around select.select() that ignores signals. If
+        select.select raises a select.error exception and errno is an EINTR
+        error then it is ignored. Mainly this is used to ignore sigwinch
+        (terminal resize). '''
+
+        # if select() is interrupted by a signal (errno==EINTR) then
+        # we loop back and enter the select() again.
+        if timeout is not None:
+            end_time = time.time() + timeout
+        while True:
+            try:
+                return select.select(iwtd, owtd, ewtd, timeout)
+            except select.error:
+                err = sys.exc_info()[1]
+                if err.errno == errno.EINTR:
+                    # if we loop back we have to subtract the
+                    # amount of time we already waited.
+                    if timeout is not None:
+                        timeout = end_time - time.time()
+                        if timeout < 0:
+                            return([], [], [])
+                else:
+                    # something else caused the select.error, so
+                    # this actually is an exception.
+                    raise
+
+##############################################################################
+# The following methods are no longer supported or allowed.
+
+    def setmaxread(self, maxread):
+
+        '''This method is no longer supported or allowed. I don't like getters
+        and setters without a good reason. '''
+
+        raise ExceptionPexpect('This method is no longer supported ' +
+                'or allowed. Just assign a value to the ' +
+                'maxread member variable.')
+
+    def setlog(self, fileobject):
+
+        '''This method is no longer supported or allowed.
+        '''
+
+        raise ExceptionPexpect('This method is no longer supported ' +
+                'or allowed. Just assign a value to the logfile ' +
+                'member variable.')
+
+##############################################################################
+# End of spawn class
+##############################################################################
+
+class spawnu(spawn):
+    """Works like spawn, but accepts and returns unicode strings.
+
+    Extra parameters:
+
+    :param encoding: The encoding to use for communications (default: 'utf-8')
+    :param errors: How to handle encoding/decoding errors; one of 'strict'
+                   (the default), 'ignore', or 'replace', as described
+                   for :meth:`~bytes.decode` and :meth:`~str.encode`.
+    """
+    if PY3:
+        string_type = str
+        allowed_string_types = (str, )
+        _chr = staticmethod(chr)
+        linesep = os.linesep
+    else:
+        string_type = unicode
+        allowed_string_types = (unicode, )
+        _chr = staticmethod(unichr)
+        linesep = os.linesep.decode('ascii')
+    # This can handle unicode in both Python 2 and 3
+    write_to_stdout = sys.stdout.write
+
+    def __init__(self, *args, **kwargs):
+        self.encoding = kwargs.pop('encoding', 'utf-8')
+        self.errors = kwargs.pop('errors', 'strict')
+        self._decoder = codecs.getincrementaldecoder(self.encoding)(errors=self.errors)
+        super(spawnu, self).__init__(*args, **kwargs)
+
+    @staticmethod
+    def _coerce_expect_string(s):
+        return s
+
+    @staticmethod
+    def _coerce_send_string(s):
+        return s
+
+    def _coerce_read_string(self, s):
+        return self._decoder.decode(s, final=False)
+
+    def _send(self, s):
+        return os.write(self.child_fd, s.encode(self.encoding, self.errors))
+
+
+class searcher_string(object):
+
+    '''This is a plain string search helper for the spawn.expect_any() method.
+    This helper class is for speed. For more powerful regex patterns
+    see the helper class, searcher_re.
+
+    Attributes:
+
+        eof_index     - index of EOF, or -1
+        timeout_index - index of TIMEOUT, or -1
+
+    After a successful match by the search() method the following attributes
+    are available:
+
+        start - index into the buffer, first byte of match
+        end   - index into the buffer, first byte after match
+        match - the matching string itself
+
+    '''
+
+    def __init__(self, strings):
+
+        '''This creates an instance of searcher_string. This argument 'strings'
+        may be a list; a sequence of strings; or the EOF or TIMEOUT types. '''
+
+        self.eof_index = -1
+        self.timeout_index = -1
+        self._strings = []
+        for n, s in enumerate(strings):
+            if s is EOF:
+                self.eof_index = n
+                continue
+            if s is TIMEOUT:
+                self.timeout_index = n
+                continue
+            self._strings.append((n, s))
+
+    def __str__(self):
+
+        '''This returns a human-readable string that represents the state of
+        the object.'''
+
+        ss = [(ns[0], '    %d: "%s"' % ns) for ns in self._strings]
+        ss.append((-1, 'searcher_string:'))
+        if self.eof_index >= 0:
+            ss.append((self.eof_index, '    %d: EOF' % self.eof_index))
+        if self.timeout_index >= 0:
+            ss.append((self.timeout_index,
+                '    %d: TIMEOUT' % self.timeout_index))
+        ss.sort()
+        ss = list(zip(*ss))[1]
+        return '\n'.join(ss)
+
+    def search(self, buffer, freshlen, searchwindowsize=None):
+
+        '''This searches 'buffer' for the first occurence of one of the search
+        strings.  'freshlen' must indicate the number of bytes at the end of
+        'buffer' which have not been searched before. It helps to avoid
+        searching the same, possibly big, buffer over and over again.
+
+        See class spawn for the 'searchwindowsize' argument.
+
+        If there is a match this returns the index of that string, and sets
+        'start', 'end' and 'match'. Otherwise, this returns -1. '''
+
+        first_match = None
+
+        # 'freshlen' helps a lot here. Further optimizations could
+        # possibly include:
+        #
+        # using something like the Boyer-Moore Fast String Searching
+        # Algorithm; pre-compiling the search through a list of
+        # strings into something that can scan the input once to
+        # search for all N strings; realize that if we search for
+        # ['bar', 'baz'] and the input is '...foo' we need not bother
+        # rescanning until we've read three more bytes.
+        #
+        # Sadly, I don't know enough about this interesting topic. /grahn
+
+        for index, s in self._strings:
+            if searchwindowsize is None:
+                # the match, if any, can only be in the fresh data,
+                # or at the very end of the old data
+                offset = -(freshlen + len(s))
+            else:
+                # better obey searchwindowsize
+                offset = -searchwindowsize
+            n = buffer.find(s, offset)
+            if n >= 0 and (first_match is None or n < first_match):
+                first_match = n
+                best_index, best_match = index, s
+        if first_match is None:
+            return -1
+        self.match = best_match
+        self.start = first_match
+        self.end = self.start + len(self.match)
+        return best_index
+
+
+class searcher_re(object):
+
+    '''This is regular expression string search helper for the
+    spawn.expect_any() method. This helper class is for powerful
+    pattern matching. For speed, see the helper class, searcher_string.
+
+    Attributes:
+
+        eof_index     - index of EOF, or -1
+        timeout_index - index of TIMEOUT, or -1
+
+    After a successful match by the search() method the following attributes
+    are available:
+
+        start - index into the buffer, first byte of match
+        end   - index into the buffer, first byte after match
+        match - the re.match object returned by a succesful re.search
+
+    '''
+
+    def __init__(self, patterns):
+
+        '''This creates an instance that searches for 'patterns' Where
+        'patterns' may be a list or other sequence of compiled regular
+        expressions, or the EOF or TIMEOUT types.'''
+
+        self.eof_index = -1
+        self.timeout_index = -1
+        self._searches = []
+        for n, s in zip(list(range(len(patterns))), patterns):
+            if s is EOF:
+                self.eof_index = n
+                continue
+            if s is TIMEOUT:
+                self.timeout_index = n
+                continue
+            self._searches.append((n, s))
+
+    def __str__(self):
+
+        '''This returns a human-readable string that represents the state of
+        the object.'''
+
+        #ss = [(n, '    %d: re.compile("%s")' %
+        #    (n, repr(s.pattern))) for n, s in self._searches]
+        ss = list()
+        for n, s in self._searches:
+            try:
+                ss.append((n, '    %d: re.compile("%s")' % (n, s.pattern)))
+            except UnicodeEncodeError:
+                # for test cases that display __str__ of searches, dont throw
+                # another exception just because stdout is ascii-only, using
+                # repr()
+                ss.append((n, '    %d: re.compile(%r)' % (n, s.pattern)))
+        ss.append((-1, 'searcher_re:'))
+        if self.eof_index >= 0:
+            ss.append((self.eof_index, '    %d: EOF' % self.eof_index))
+        if self.timeout_index >= 0:
+            ss.append((self.timeout_index, '    %d: TIMEOUT' %
+                self.timeout_index))
+        ss.sort()
+        ss = list(zip(*ss))[1]
+        return '\n'.join(ss)
+
+    def search(self, buffer, freshlen, searchwindowsize=None):
+
+        '''This searches 'buffer' for the first occurence of one of the regular
+        expressions. 'freshlen' must indicate the number of bytes at the end of
+        'buffer' which have not been searched before.
+
+        See class spawn for the 'searchwindowsize' argument.
+
+        If there is a match this returns the index of that string, and sets
+        'start', 'end' and 'match'. Otherwise, returns -1.'''
+
+        first_match = None
+        # 'freshlen' doesn't help here -- we cannot predict the
+        # length of a match, and the re module provides no help.
+        if searchwindowsize is None:
+            searchstart = 0
+        else:
+            searchstart = max(0, len(buffer) - searchwindowsize)
+        for index, s in self._searches:
+            match = s.search(buffer, searchstart)
+            if match is None:
+                continue
+            n = match.start()
+            if first_match is None or n < first_match:
+                first_match = n
+                the_match = match
+                best_index = index
+        if first_match is None:
+            return -1
+        self.start = first_match
+        self.match = the_match
+        self.end = self.match.end()
+        return best_index
+
+
+def which(filename):
+
+    '''This takes a given filename; tries to find it in the environment path;
+    then checks if it is executable. This returns the full path to the filename
+    if found and executable. Otherwise this returns None.'''
+
+    # Special case where filename contains an explicit path.
+    if os.path.dirname(filename) != '':
+        if os.access(filename, os.X_OK):
+            return filename
+    if 'PATH' not in os.environ or os.environ['PATH'] == '':
+        p = os.defpath
+    else:
+        p = os.environ['PATH']
+    pathlist = p.split(os.pathsep)
+    for path in pathlist:
+        ff = os.path.join(path, filename)
+        if os.access(ff, os.X_OK):
+            return ff
+    return None
+
+
+def split_command_line(command_line):
+
+    '''This splits a command line into a list of arguments. It splits arguments
+    on spaces, but handles embedded quotes, doublequotes, and escaped
+    characters. It's impossible to do this with a regular expression, so I
+    wrote a little state machine to parse the command line. '''
+
+    arg_list = []
+    arg = ''
+
+    # Constants to name the states we can be in.
+    state_basic = 0
+    state_esc = 1
+    state_singlequote = 2
+    state_doublequote = 3
+    # The state when consuming whitespace between commands.
+    state_whitespace = 4
+    state = state_basic
+
+    for c in command_line:
+        if state == state_basic or state == state_whitespace:
+            if c == '\\':
+                # Escape the next character
+                state = state_esc
+            elif c == r"'":
+                # Handle single quote
+                state = state_singlequote
+            elif c == r'"':
+                # Handle double quote
+                state = state_doublequote
+            elif c.isspace():
+                # Add arg to arg_list if we aren't in the middle of whitespace.
+                if state == state_whitespace:
+                    # Do nothing.
+                    None
+                else:
+                    arg_list.append(arg)
+                    arg = ''
+                    state = state_whitespace
+            else:
+                arg = arg + c
+                state = state_basic
+        elif state == state_esc:
+            arg = arg + c
+            state = state_basic
+        elif state == state_singlequote:
+            if c == r"'":
+                state = state_basic
+            else:
+                arg = arg + c
+        elif state == state_doublequote:
+            if c == r'"':
+                state = state_basic
+            else:
+                arg = arg + c
+
+    if arg != '':
+        arg_list.append(arg)
+    return arg_list
+
+# vi:set sr et ts=4 sw=4 ft=python :

=== modified file 'debian/changelog'
--- debian/changelog	2014-01-26 11:22:03 +0000
+++ debian/changelog	2014-05-08 13:59:49 +0000
@@ -1,3 +1,9 @@
+pexpect (3.1-1ubuntu1) UNRELEASED; urgency=medium
+
+  * Add patch errno_handling_fix to fix interruption handling bug
+
+ -- Stéphane Duchesneau <[e-mail]>  Thu, 08 May 2014 09:45:52 -0400
+
 pexpect (3.1-1) unstable; urgency=medium
 
   * Team upload.

=== added directory 'debian/patches'
=== added file 'debian/patches/errno_handling_fix.patch'
--- debian/patches/errno_handling_fix.patch	1970-01-01 00:00:00 +0000
+++ debian/patches/errno_handling_fix.patch	2014-05-08 13:59:49 +0000
@@ -0,0 +1,13 @@
+Index: pexpect.dev/pexpect/__init__.py
+===================================================================
+--- pexpect.dev.orig/pexpect/__init__.py	2014-05-08 09:44:22.130208000 -0400
++++ pexpect.dev/pexpect/__init__.py	2014-05-08 09:44:53.147617432 -0400
+@@ -1687,7 +1687,7 @@
+                 return select.select(iwtd, owtd, ewtd, timeout)
+             except select.error:
+                 err = sys.exc_info()[1]
+-                if err.errno == errno.EINTR:
++                if err[0] == errno.EINTR:
+                     # if we loop back we have to subtract the
+                     # amount of time we already waited.
+                     if timeout is not None:

=== added file 'debian/patches/series'
--- debian/patches/series	1970-01-01 00:00:00 +0000
+++ debian/patches/series	2014-05-08 13:59:49 +0000
@@ -0,0 +1,1 @@
+errno_handling_fix.patch

=== modified file 'pexpect/__init__.py'
--- pexpect/__init__.py	2014-01-26 11:22:03 +0000
+++ pexpect/__init__.py	2014-05-08 13:59:49 +0000
@@ -1687,7 +1687,7 @@
                 return select.select(iwtd, owtd, ewtd, timeout)
             except select.error:
                 err = sys.exc_info()[1]
-                if err.errno == errno.EINTR:
+                if err[0] == errno.EINTR:
                     # if we loop back we have to subtract the
                     # amount of time we already waited.
                     if timeout is not None: