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Jason R. Coombs committed 682f27f Merge

Merge with 3.2.x

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cherrypy/_cpcompat.py

 
     if sys.version_info < (2,6):
         daemon = property(__get_daemon, __set_daemon)
+
+# Use subprocess module from Python 2.7 on Python 2.3-2.6
+if sys.version_info < (2,7):
+    import cherrypy._cpcompat_subprocess as subprocess
+else:
+    import subprocess

cherrypy/_cpcompat_subprocess.py

+# subprocess - Subprocesses with accessible I/O streams
+#
+# For more information about this module, see PEP 324.
+#
+# This module should remain compatible with Python 2.2, see PEP 291.
+#
+# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
+#
+# Licensed to PSF under a Contributor Agreement.
+# See http://www.python.org/2.4/license for licensing details.
+
+r"""subprocess - Subprocesses with accessible I/O streams
+
+This module allows you to spawn processes, connect to their
+input/output/error pipes, and obtain their return codes.  This module
+intends to replace several other, older modules and functions, like:
+
+os.system
+os.spawn*
+os.popen*
+popen2.*
+commands.*
+
+Information about how the subprocess module can be used to replace these
+modules and functions can be found below.
+
+
+
+Using the subprocess module
+===========================
+This module defines one class called Popen:
+
+class Popen(args, bufsize=0, executable=None,
+            stdin=None, stdout=None, stderr=None,
+            preexec_fn=None, close_fds=False, shell=False,
+            cwd=None, env=None, universal_newlines=False,
+            startupinfo=None, creationflags=0):
+
+
+Arguments are:
+
+args should be a string, or a sequence of program arguments.  The
+program to execute is normally the first item in the args sequence or
+string, but can be explicitly set by using the executable argument.
+
+On UNIX, with shell=False (default): In this case, the Popen class
+uses os.execvp() to execute the child program.  args should normally
+be a sequence.  A string will be treated as a sequence with the string
+as the only item (the program to execute).
+
+On UNIX, with shell=True: If args is a string, it specifies the
+command string to execute through the shell.  If args is a sequence,
+the first item specifies the command string, and any additional items
+will be treated as additional shell arguments.
+
+On Windows: the Popen class uses CreateProcess() to execute the child
+program, which operates on strings.  If args is a sequence, it will be
+converted to a string using the list2cmdline method.  Please note that
+not all MS Windows applications interpret the command line the same
+way: The list2cmdline is designed for applications using the same
+rules as the MS C runtime.
+
+bufsize, if given, has the same meaning as the corresponding argument
+to the built-in open() function: 0 means unbuffered, 1 means line
+buffered, any other positive value means use a buffer of
+(approximately) that size.  A negative bufsize means to use the system
+default, which usually means fully buffered.  The default value for
+bufsize is 0 (unbuffered).
+
+stdin, stdout and stderr specify the executed programs' standard
+input, standard output and standard error file handles, respectively.
+Valid values are PIPE, an existing file descriptor (a positive
+integer), an existing file object, and None.  PIPE indicates that a
+new pipe to the child should be created.  With None, no redirection
+will occur; the child's file handles will be inherited from the
+parent.  Additionally, stderr can be STDOUT, which indicates that the
+stderr data from the applications should be captured into the same
+file handle as for stdout.
+
+If preexec_fn is set to a callable object, this object will be called
+in the child process just before the child is executed.
+
+If close_fds is true, all file descriptors except 0, 1 and 2 will be
+closed before the child process is executed.
+
+if shell is true, the specified command will be executed through the
+shell.
+
+If cwd is not None, the current directory will be changed to cwd
+before the child is executed.
+
+If env is not None, it defines the environment variables for the new
+process.
+
+If universal_newlines is true, the file objects stdout and stderr are
+opened as a text files, but lines may be terminated by any of '\n',
+the Unix end-of-line convention, '\r', the Macintosh convention or
+'\r\n', the Windows convention.  All of these external representations
+are seen as '\n' by the Python program.  Note: This feature is only
+available if Python is built with universal newline support (the
+default).  Also, the newlines attribute of the file objects stdout,
+stdin and stderr are not updated by the communicate() method.
+
+The startupinfo and creationflags, if given, will be passed to the
+underlying CreateProcess() function.  They can specify things such as
+appearance of the main window and priority for the new process.
+(Windows only)
+
+
+This module also defines some shortcut functions:
+
+call(*popenargs, **kwargs):
+    Run command with arguments.  Wait for command to complete, then
+    return the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    retcode = call(["ls", "-l"])
+
+check_call(*popenargs, **kwargs):
+    Run command with arguments.  Wait for command to complete.  If the
+    exit code was zero then return, otherwise raise
+    CalledProcessError.  The CalledProcessError object will have the
+    return code in the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    check_call(["ls", "-l"])
+
+check_output(*popenargs, **kwargs):
+    Run command with arguments and return its output as a byte string.
+
+    If the exit code was non-zero it raises a CalledProcessError.  The
+    CalledProcessError object will have the return code in the returncode
+    attribute and output in the output attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    output = check_output(["ls", "-l", "/dev/null"])
+
+
+Exceptions
+----------
+Exceptions raised in the child process, before the new program has
+started to execute, will be re-raised in the parent.  Additionally,
+the exception object will have one extra attribute called
+'child_traceback', which is a string containing traceback information
+from the childs point of view.
+
+The most common exception raised is OSError.  This occurs, for
+example, when trying to execute a non-existent file.  Applications
+should prepare for OSErrors.
+
+A ValueError will be raised if Popen is called with invalid arguments.
+
+check_call() and check_output() will raise CalledProcessError, if the
+called process returns a non-zero return code.
+
+
+Security
+--------
+Unlike some other popen functions, this implementation will never call
+/bin/sh implicitly.  This means that all characters, including shell
+metacharacters, can safely be passed to child processes.
+
+
+Popen objects
+=============
+Instances of the Popen class have the following methods:
+
+poll()
+    Check if child process has terminated.  Returns returncode
+    attribute.
+
+wait()
+    Wait for child process to terminate.  Returns returncode attribute.
+
+communicate(input=None)
+    Interact with process: Send data to stdin.  Read data from stdout
+    and stderr, until end-of-file is reached.  Wait for process to
+    terminate.  The optional input argument should be a string to be
+    sent to the child process, or None, if no data should be sent to
+    the child.
+
+    communicate() returns a tuple (stdout, stderr).
+
+    Note: The data read is buffered in memory, so do not use this
+    method if the data size is large or unlimited.
+
+The following attributes are also available:
+
+stdin
+    If the stdin argument is PIPE, this attribute is a file object
+    that provides input to the child process.  Otherwise, it is None.
+
+stdout
+    If the stdout argument is PIPE, this attribute is a file object
+    that provides output from the child process.  Otherwise, it is
+    None.
+
+stderr
+    If the stderr argument is PIPE, this attribute is file object that
+    provides error output from the child process.  Otherwise, it is
+    None.
+
+pid
+    The process ID of the child process.
+
+returncode
+    The child return code.  A None value indicates that the process
+    hasn't terminated yet.  A negative value -N indicates that the
+    child was terminated by signal N (UNIX only).
+
+
+Replacing older functions with the subprocess module
+====================================================
+In this section, "a ==> b" means that b can be used as a replacement
+for a.
+
+Note: All functions in this section fail (more or less) silently if
+the executed program cannot be found; this module raises an OSError
+exception.
+
+In the following examples, we assume that the subprocess module is
+imported with "from subprocess import *".
+
+
+Replacing /bin/sh shell backquote
+---------------------------------
+output=`mycmd myarg`
+==>
+output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0]
+
+
+Replacing shell pipe line
+-------------------------
+output=`dmesg | grep hda`
+==>
+p1 = Popen(["dmesg"], stdout=PIPE)
+p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
+output = p2.communicate()[0]
+
+
+Replacing os.system()
+---------------------
+sts = os.system("mycmd" + " myarg")
+==>
+p = Popen("mycmd" + " myarg", shell=True)
+pid, sts = os.waitpid(p.pid, 0)
+
+Note:
+
+* Calling the program through the shell is usually not required.
+
+* It's easier to look at the returncode attribute than the
+  exitstatus.
+
+A more real-world example would look like this:
+
+try:
+    retcode = call("mycmd" + " myarg", shell=True)
+    if retcode < 0:
+        print >>sys.stderr, "Child was terminated by signal", -retcode
+    else:
+        print >>sys.stderr, "Child returned", retcode
+except OSError, e:
+    print >>sys.stderr, "Execution failed:", e
+
+
+Replacing os.spawn*
+-------------------
+P_NOWAIT example:
+
+pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg")
+==>
+pid = Popen(["/bin/mycmd", "myarg"]).pid
+
+
+P_WAIT example:
+
+retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg")
+==>
+retcode = call(["/bin/mycmd", "myarg"])
+
+
+Vector example:
+
+os.spawnvp(os.P_NOWAIT, path, args)
+==>
+Popen([path] + args[1:])
+
+
+Environment example:
+
+os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env)
+==>
+Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"})
+
+
+Replacing os.popen*
+-------------------
+pipe = os.popen("cmd", mode='r', bufsize)
+==>
+pipe = Popen("cmd", shell=True, bufsize=bufsize, stdout=PIPE).stdout
+
+pipe = os.popen("cmd", mode='w', bufsize)
+==>
+pipe = Popen("cmd", shell=True, bufsize=bufsize, stdin=PIPE).stdin
+
+
+(child_stdin, child_stdout) = os.popen2("cmd", mode, bufsize)
+==>
+p = Popen("cmd", shell=True, bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, close_fds=True)
+(child_stdin, child_stdout) = (p.stdin, p.stdout)
+
+
+(child_stdin,
+ child_stdout,
+ child_stderr) = os.popen3("cmd", mode, bufsize)
+==>
+p = Popen("cmd", shell=True, bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, stderr=PIPE, close_fds=True)
+(child_stdin,
+ child_stdout,
+ child_stderr) = (p.stdin, p.stdout, p.stderr)
+
+
+(child_stdin, child_stdout_and_stderr) = os.popen4("cmd", mode,
+                                                   bufsize)
+==>
+p = Popen("cmd", shell=True, bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True)
+(child_stdin, child_stdout_and_stderr) = (p.stdin, p.stdout)
+
+On Unix, os.popen2, os.popen3 and os.popen4 also accept a sequence as
+the command to execute, in which case arguments will be passed
+directly to the program without shell intervention.  This usage can be
+replaced as follows:
+
+(child_stdin, child_stdout) = os.popen2(["/bin/ls", "-l"], mode,
+                                        bufsize)
+==>
+p = Popen(["/bin/ls", "-l"], bufsize=bufsize, stdin=PIPE, stdout=PIPE)
+(child_stdin, child_stdout) = (p.stdin, p.stdout)
+
+Return code handling translates as follows:
+
+pipe = os.popen("cmd", 'w')
+...
+rc = pipe.close()
+if rc is not None and rc % 256:
+    print "There were some errors"
+==>
+process = Popen("cmd", 'w', shell=True, stdin=PIPE)
+...
+process.stdin.close()
+if process.wait() != 0:
+    print "There were some errors"
+
+
+Replacing popen2.*
+------------------
+(child_stdout, child_stdin) = popen2.popen2("somestring", bufsize, mode)
+==>
+p = Popen(["somestring"], shell=True, bufsize=bufsize
+          stdin=PIPE, stdout=PIPE, close_fds=True)
+(child_stdout, child_stdin) = (p.stdout, p.stdin)
+
+On Unix, popen2 also accepts a sequence as the command to execute, in
+which case arguments will be passed directly to the program without
+shell intervention.  This usage can be replaced as follows:
+
+(child_stdout, child_stdin) = popen2.popen2(["mycmd", "myarg"], bufsize,
+                                            mode)
+==>
+p = Popen(["mycmd", "myarg"], bufsize=bufsize,
+          stdin=PIPE, stdout=PIPE, close_fds=True)
+(child_stdout, child_stdin) = (p.stdout, p.stdin)
+
+The popen2.Popen3 and popen2.Popen4 basically works as subprocess.Popen,
+except that:
+
+* subprocess.Popen raises an exception if the execution fails
+* the capturestderr argument is replaced with the stderr argument.
+* stdin=PIPE and stdout=PIPE must be specified.
+* popen2 closes all filedescriptors by default, but you have to specify
+  close_fds=True with subprocess.Popen.
+"""
+
+import sys
+mswindows = (sys.platform == "win32")
+
+import os
+import types
+import traceback
+import gc
+import signal
+import errno
+
+# Exception classes used by this module.
+class CalledProcessError(Exception):
+    """This exception is raised when a process run by check_call() or
+    check_output() returns a non-zero exit status.
+    The exit status will be stored in the returncode attribute;
+    check_output() will also store the output in the output attribute.
+    """
+    def __init__(self, returncode, cmd, output=None):
+        self.returncode = returncode
+        self.cmd = cmd
+        self.output = output
+    def __str__(self):
+        return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
+
+
+if mswindows:
+    import threading
+    import msvcrt
+    import _subprocess
+    class STARTUPINFO:
+        dwFlags = 0
+        hStdInput = None
+        hStdOutput = None
+        hStdError = None
+        wShowWindow = 0
+    class pywintypes:
+        error = IOError
+else:
+    import select
+    _has_poll = hasattr(select, 'poll')
+    import fcntl
+    import pickle
+
+    # When select or poll has indicated that the file is writable,
+    # we can write up to _PIPE_BUF bytes without risk of blocking.
+    # POSIX defines PIPE_BUF as >= 512.
+    _PIPE_BUF = getattr(select, 'PIPE_BUF', 512)
+
+
+__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call",
+           "check_output", "CalledProcessError"]
+
+if mswindows:
+    from _subprocess import (CREATE_NEW_CONSOLE, CREATE_NEW_PROCESS_GROUP,
+                             STD_INPUT_HANDLE, STD_OUTPUT_HANDLE,
+                             STD_ERROR_HANDLE, SW_HIDE,
+                             STARTF_USESTDHANDLES, STARTF_USESHOWWINDOW)
+
+    __all__.extend(["CREATE_NEW_CONSOLE", "CREATE_NEW_PROCESS_GROUP",
+                    "STD_INPUT_HANDLE", "STD_OUTPUT_HANDLE",
+                    "STD_ERROR_HANDLE", "SW_HIDE",
+                    "STARTF_USESTDHANDLES", "STARTF_USESHOWWINDOW"])
+try:
+    MAXFD = os.sysconf("SC_OPEN_MAX")
+except:
+    MAXFD = 256
+
+_active = []
+
+def _cleanup():
+    for inst in _active[:]:
+        res = inst._internal_poll(_deadstate=sys.maxint)
+        if res is not None:
+            try:
+                _active.remove(inst)
+            except ValueError:
+                # This can happen if two threads create a new Popen instance.
+                # It's harmless that it was already removed, so ignore.
+                pass
+
+PIPE = -1
+STDOUT = -2
+
+
+def _eintr_retry_call(func, *args):
+    while True:
+        try:
+            return func(*args)
+        except (OSError, IOError) as e:
+            if e.errno == errno.EINTR:
+                continue
+            raise
+
+
+def call(*popenargs, **kwargs):
+    """Run command with arguments.  Wait for command to complete, then
+    return the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    retcode = call(["ls", "-l"])
+    """
+    return Popen(*popenargs, **kwargs).wait()
+
+
+def check_call(*popenargs, **kwargs):
+    """Run command with arguments.  Wait for command to complete.  If
+    the exit code was zero then return, otherwise raise
+    CalledProcessError.  The CalledProcessError object will have the
+    return code in the returncode attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    check_call(["ls", "-l"])
+    """
+    retcode = call(*popenargs, **kwargs)
+    if retcode:
+        cmd = kwargs.get("args")
+        if cmd is None:
+            cmd = popenargs[0]
+        raise CalledProcessError(retcode, cmd)
+    return 0
+
+
+def check_output(*popenargs, **kwargs):
+    r"""Run command with arguments and return its output as a byte string.
+
+    If the exit code was non-zero it raises a CalledProcessError.  The
+    CalledProcessError object will have the return code in the returncode
+    attribute and output in the output attribute.
+
+    The arguments are the same as for the Popen constructor.  Example:
+
+    >>> check_output(["ls", "-l", "/dev/null"])
+    'crw-rw-rw- 1 root root 1, 3 Oct 18  2007 /dev/null\n'
+
+    The stdout argument is not allowed as it is used internally.
+    To capture standard error in the result, use stderr=STDOUT.
+
+    >>> check_output(["/bin/sh", "-c",
+    ...               "ls -l non_existent_file ; exit 0"],
+    ...              stderr=STDOUT)
+    'ls: non_existent_file: No such file or directory\n'
+    """
+    if 'stdout' in kwargs:
+        raise ValueError('stdout argument not allowed, it will be overridden.')
+    process = Popen(stdout=PIPE, *popenargs, **kwargs)
+    output, unused_err = process.communicate()
+    retcode = process.poll()
+    if retcode:
+        cmd = kwargs.get("args")
+        if cmd is None:
+            cmd = popenargs[0]
+        raise CalledProcessError(retcode, cmd, output=output)
+    return output
+
+
+def list2cmdline(seq):
+    """
+    Translate a sequence of arguments into a command line
+    string, using the same rules as the MS C runtime:
+
+    1) Arguments are delimited by white space, which is either a
+       space or a tab.
+
+    2) A string surrounded by double quotation marks is
+       interpreted as a single argument, regardless of white space
+       contained within.  A quoted string can be embedded in an
+       argument.
+
+    3) A double quotation mark preceded by a backslash is
+       interpreted as a literal double quotation mark.
+
+    4) Backslashes are interpreted literally, unless they
+       immediately precede a double quotation mark.
+
+    5) If backslashes immediately precede a double quotation mark,
+       every pair of backslashes is interpreted as a literal
+       backslash.  If the number of backslashes is odd, the last
+       backslash escapes the next double quotation mark as
+       described in rule 3.
+    """
+
+    # See
+    # http://msdn.microsoft.com/en-us/library/17w5ykft.aspx
+    # or search http://msdn.microsoft.com for
+    # "Parsing C++ Command-Line Arguments"
+    result = []
+    needquote = False
+    for arg in seq:
+        bs_buf = []
+
+        # Add a space to separate this argument from the others
+        if result:
+            result.append(' ')
+
+        needquote = (" " in arg) or ("\t" in arg) or not arg
+        if needquote:
+            result.append('"')
+
+        for c in arg:
+            if c == '\\':
+                # Don't know if we need to double yet.
+                bs_buf.append(c)
+            elif c == '"':
+                # Double backslashes.
+                result.append('\\' * len(bs_buf)*2)
+                bs_buf = []
+                result.append('\\"')
+            else:
+                # Normal char
+                if bs_buf:
+                    result.extend(bs_buf)
+                    bs_buf = []
+                result.append(c)
+
+        # Add remaining backslashes, if any.
+        if bs_buf:
+            result.extend(bs_buf)
+
+        if needquote:
+            result.extend(bs_buf)
+            result.append('"')
+
+    return ''.join(result)
+
+
+class Popen(object):
+    def __init__(self, args, bufsize=0, executable=None,
+                 stdin=None, stdout=None, stderr=None,
+                 preexec_fn=None, close_fds=False, shell=False,
+                 cwd=None, env=None, universal_newlines=False,
+                 startupinfo=None, creationflags=0):
+        """Create new Popen instance."""
+        _cleanup()
+
+        self._child_created = False
+        if not isinstance(bufsize, (int, long)):
+            raise TypeError("bufsize must be an integer")
+
+        if mswindows:
+            if preexec_fn is not None:
+                raise ValueError("preexec_fn is not supported on Windows "
+                                 "platforms")
+            if close_fds and (stdin is not None or stdout is not None or
+                              stderr is not None):
+                raise ValueError("close_fds is not supported on Windows "
+                                 "platforms if you redirect stdin/stdout/stderr")
+        else:
+            # POSIX
+            if startupinfo is not None:
+                raise ValueError("startupinfo is only supported on Windows "
+                                 "platforms")
+            if creationflags != 0:
+                raise ValueError("creationflags is only supported on Windows "
+                                 "platforms")
+
+        self.stdin = None
+        self.stdout = None
+        self.stderr = None
+        self.pid = None
+        self.returncode = None
+        self.universal_newlines = universal_newlines
+
+        # Input and output objects. The general principle is like
+        # this:
+        #
+        # Parent                   Child
+        # ------                   -----
+        # p2cwrite   ---stdin--->  p2cread
+        # c2pread    <--stdout---  c2pwrite
+        # errread    <--stderr---  errwrite
+        #
+        # On POSIX, the child objects are file descriptors.  On
+        # Windows, these are Windows file handles.  The parent objects
+        # are file descriptors on both platforms.  The parent objects
+        # are None when not using PIPEs. The child objects are None
+        # when not redirecting.
+
+        (p2cread, p2cwrite,
+         c2pread, c2pwrite,
+         errread, errwrite) = self._get_handles(stdin, stdout, stderr)
+
+        self._execute_child(args, executable, preexec_fn, close_fds,
+                            cwd, env, universal_newlines,
+                            startupinfo, creationflags, shell,
+                            p2cread, p2cwrite,
+                            c2pread, c2pwrite,
+                            errread, errwrite)
+
+        if mswindows:
+            if p2cwrite is not None:
+                p2cwrite = msvcrt.open_osfhandle(p2cwrite.Detach(), 0)
+            if c2pread is not None:
+                c2pread = msvcrt.open_osfhandle(c2pread.Detach(), 0)
+            if errread is not None:
+                errread = msvcrt.open_osfhandle(errread.Detach(), 0)
+
+        if p2cwrite is not None:
+            self.stdin = os.fdopen(p2cwrite, 'wb', bufsize)
+        if c2pread is not None:
+            if universal_newlines:
+                self.stdout = os.fdopen(c2pread, 'rU', bufsize)
+            else:
+                self.stdout = os.fdopen(c2pread, 'rb', bufsize)
+        if errread is not None:
+            if universal_newlines:
+                self.stderr = os.fdopen(errread, 'rU', bufsize)
+            else:
+                self.stderr = os.fdopen(errread, 'rb', bufsize)
+
+
+    def _translate_newlines(self, data):
+        data = data.replace("\r\n", "\n")
+        data = data.replace("\r", "\n")
+        return data
+
+
+    def __del__(self, _maxint=sys.maxint, _active=_active):
+        # If __init__ hasn't had a chance to execute (e.g. if it
+        # was passed an undeclared keyword argument), we don't
+        # have a _child_created attribute at all.
+        if not getattr(self, '_child_created', False):
+            # We didn't get to successfully create a child process.
+            return
+        # In case the child hasn't been waited on, check if it's done.
+        self._internal_poll(_deadstate=_maxint)
+        if self.returncode is None and _active is not None:
+            # Child is still running, keep us alive until we can wait on it.
+            _active.append(self)
+
+
+    def communicate(self, input=None):
+        """Interact with process: Send data to stdin.  Read data from
+        stdout and stderr, until end-of-file is reached.  Wait for
+        process to terminate.  The optional input argument should be a
+        string to be sent to the child process, or None, if no data
+        should be sent to the child.
+
+        communicate() returns a tuple (stdout, stderr)."""
+
+        # Optimization: If we are only using one pipe, or no pipe at
+        # all, using select() or threads is unnecessary.
+        if [self.stdin, self.stdout, self.stderr].count(None) >= 2:
+            stdout = None
+            stderr = None
+            if self.stdin:
+                if input:
+                    try:
+                        self.stdin.write(input)
+                    except IOError as e:
+                        if e.errno != errno.EPIPE and e.errno != errno.EINVAL:
+                            raise
+                self.stdin.close()
+            elif self.stdout:
+                stdout = _eintr_retry_call(self.stdout.read)
+                self.stdout.close()
+            elif self.stderr:
+                stderr = _eintr_retry_call(self.stderr.read)
+                self.stderr.close()
+            self.wait()
+            return (stdout, stderr)
+
+        return self._communicate(input)
+
+
+    def poll(self):
+        return self._internal_poll()
+
+
+    if mswindows:
+        #
+        # Windows methods
+        #
+        def _get_handles(self, stdin, stdout, stderr):
+            """Construct and return tuple with IO objects:
+            p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
+            """
+            if stdin is None and stdout is None and stderr is None:
+                return (None, None, None, None, None, None)
+
+            p2cread, p2cwrite = None, None
+            c2pread, c2pwrite = None, None
+            errread, errwrite = None, None
+
+            if stdin is None:
+                p2cread = _subprocess.GetStdHandle(_subprocess.STD_INPUT_HANDLE)
+                if p2cread is None:
+                    p2cread, _ = _subprocess.CreatePipe(None, 0)
+            elif stdin == PIPE:
+                p2cread, p2cwrite = _subprocess.CreatePipe(None, 0)
+            elif isinstance(stdin, int):
+                p2cread = msvcrt.get_osfhandle(stdin)
+            else:
+                # Assuming file-like object
+                p2cread = msvcrt.get_osfhandle(stdin.fileno())
+            p2cread = self._make_inheritable(p2cread)
+
+            if stdout is None:
+                c2pwrite = _subprocess.GetStdHandle(_subprocess.STD_OUTPUT_HANDLE)
+                if c2pwrite is None:
+                    _, c2pwrite = _subprocess.CreatePipe(None, 0)
+            elif stdout == PIPE:
+                c2pread, c2pwrite = _subprocess.CreatePipe(None, 0)
+            elif isinstance(stdout, int):
+                c2pwrite = msvcrt.get_osfhandle(stdout)
+            else:
+                # Assuming file-like object
+                c2pwrite = msvcrt.get_osfhandle(stdout.fileno())
+            c2pwrite = self._make_inheritable(c2pwrite)
+
+            if stderr is None:
+                errwrite = _subprocess.GetStdHandle(_subprocess.STD_ERROR_HANDLE)
+                if errwrite is None:
+                    _, errwrite = _subprocess.CreatePipe(None, 0)
+            elif stderr == PIPE:
+                errread, errwrite = _subprocess.CreatePipe(None, 0)
+            elif stderr == STDOUT:
+                errwrite = c2pwrite
+            elif isinstance(stderr, int):
+                errwrite = msvcrt.get_osfhandle(stderr)
+            else:
+                # Assuming file-like object
+                errwrite = msvcrt.get_osfhandle(stderr.fileno())
+            errwrite = self._make_inheritable(errwrite)
+
+            return (p2cread, p2cwrite,
+                    c2pread, c2pwrite,
+                    errread, errwrite)
+
+
+        def _make_inheritable(self, handle):
+            """Return a duplicate of handle, which is inheritable"""
+            return _subprocess.DuplicateHandle(_subprocess.GetCurrentProcess(),
+                                handle, _subprocess.GetCurrentProcess(), 0, 1,
+                                _subprocess.DUPLICATE_SAME_ACCESS)
+
+
+        def _find_w9xpopen(self):
+            """Find and return absolut path to w9xpopen.exe"""
+            w9xpopen = os.path.join(
+                            os.path.dirname(_subprocess.GetModuleFileName(0)),
+                                    "w9xpopen.exe")
+            if not os.path.exists(w9xpopen):
+                # Eeek - file-not-found - possibly an embedding
+                # situation - see if we can locate it in sys.exec_prefix
+                w9xpopen = os.path.join(os.path.dirname(sys.exec_prefix),
+                                        "w9xpopen.exe")
+                if not os.path.exists(w9xpopen):
+                    raise RuntimeError("Cannot locate w9xpopen.exe, which is "
+                                       "needed for Popen to work with your "
+                                       "shell or platform.")
+            return w9xpopen
+
+
+        def _execute_child(self, args, executable, preexec_fn, close_fds,
+                           cwd, env, universal_newlines,
+                           startupinfo, creationflags, shell,
+                           p2cread, p2cwrite,
+                           c2pread, c2pwrite,
+                           errread, errwrite):
+            """Execute program (MS Windows version)"""
+
+            if not isinstance(args, types.StringTypes):
+                args = list2cmdline(args)
+
+            # Process startup details
+            if startupinfo is None:
+                startupinfo = STARTUPINFO()
+            if None not in (p2cread, c2pwrite, errwrite):
+                startupinfo.dwFlags |= _subprocess.STARTF_USESTDHANDLES
+                startupinfo.hStdInput = p2cread
+                startupinfo.hStdOutput = c2pwrite
+                startupinfo.hStdError = errwrite
+
+            if shell:
+                startupinfo.dwFlags |= _subprocess.STARTF_USESHOWWINDOW
+                startupinfo.wShowWindow = _subprocess.SW_HIDE
+                comspec = os.environ.get("COMSPEC", "cmd.exe")
+                args = '{} /c "{}"'.format (comspec, args)
+                if (_subprocess.GetVersion() >= 0x80000000 or
+                        os.path.basename(comspec).lower() == "command.com"):
+                    # Win9x, or using command.com on NT. We need to
+                    # use the w9xpopen intermediate program. For more
+                    # information, see KB Q150956
+                    # (http://web.archive.org/web/20011105084002/http://support.microsoft.com/support/kb/articles/Q150/9/56.asp)
+                    w9xpopen = self._find_w9xpopen()
+                    args = '"%s" %s' % (w9xpopen, args)
+                    # Not passing CREATE_NEW_CONSOLE has been known to
+                    # cause random failures on win9x.  Specifically a
+                    # dialog: "Your program accessed mem currently in
+                    # use at xxx" and a hopeful warning about the
+                    # stability of your system.  Cost is Ctrl+C wont
+                    # kill children.
+                    creationflags |= _subprocess.CREATE_NEW_CONSOLE
+
+            # Start the process
+            try:
+                hp, ht, pid, tid = _subprocess.CreateProcess(executable, args,
+                                         # no special security
+                                         None, None,
+                                         int(not close_fds),
+                                         creationflags,
+                                         env,
+                                         cwd,
+                                         startupinfo)
+            except pywintypes.error, e:
+                # Translate pywintypes.error to WindowsError, which is
+                # a subclass of OSError.  FIXME: We should really
+                # translate errno using _sys_errlist (or similar), but
+                # how can this be done from Python?
+                raise WindowsError(*e.args)
+            finally:
+                # Child is launched. Close the parent's copy of those pipe
+                # handles that only the child should have open.  You need
+                # to make sure that no handles to the write end of the
+                # output pipe are maintained in this process or else the
+                # pipe will not close when the child process exits and the
+                # ReadFile will hang.
+                if p2cread is not None:
+                    p2cread.Close()
+                if c2pwrite is not None:
+                    c2pwrite.Close()
+                if errwrite is not None:
+                    errwrite.Close()
+
+            # Retain the process handle, but close the thread handle
+            self._child_created = True
+            self._handle = hp
+            self.pid = pid
+            ht.Close()
+
+        def _internal_poll(self, _deadstate=None,
+                _WaitForSingleObject=_subprocess.WaitForSingleObject,
+                _WAIT_OBJECT_0=_subprocess.WAIT_OBJECT_0,
+                _GetExitCodeProcess=_subprocess.GetExitCodeProcess):
+            """Check if child process has terminated.  Returns returncode
+            attribute.
+
+            This method is called by __del__, so it can only refer to objects
+            in its local scope.
+
+            """
+            if self.returncode is None:
+                if _WaitForSingleObject(self._handle, 0) == _WAIT_OBJECT_0:
+                    self.returncode = _GetExitCodeProcess(self._handle)
+            return self.returncode
+
+
+        def wait(self):
+            """Wait for child process to terminate.  Returns returncode
+            attribute."""
+            if self.returncode is None:
+                _subprocess.WaitForSingleObject(self._handle,
+                                                _subprocess.INFINITE)
+                self.returncode = _subprocess.GetExitCodeProcess(self._handle)
+            return self.returncode
+
+
+        def _readerthread(self, fh, buffer):
+            buffer.append(fh.read())
+
+
+        def _communicate(self, input):
+            stdout = None # Return
+            stderr = None # Return
+
+            if self.stdout:
+                stdout = []
+                stdout_thread = threading.Thread(target=self._readerthread,
+                                                 args=(self.stdout, stdout))
+                stdout_thread.setDaemon(True)
+                stdout_thread.start()
+            if self.stderr:
+                stderr = []
+                stderr_thread = threading.Thread(target=self._readerthread,
+                                                 args=(self.stderr, stderr))
+                stderr_thread.setDaemon(True)
+                stderr_thread.start()
+
+            if self.stdin:
+                if input is not None:
+                    try:
+                        self.stdin.write(input)
+                    except IOError as e:
+                        if e.errno != errno.EPIPE:
+                            raise
+                self.stdin.close()
+
+            if self.stdout:
+                stdout_thread.join()
+            if self.stderr:
+                stderr_thread.join()
+
+            # All data exchanged.  Translate lists into strings.
+            if stdout is not None:
+                stdout = stdout[0]
+            if stderr is not None:
+                stderr = stderr[0]
+
+            # Translate newlines, if requested.  We cannot let the file
+            # object do the translation: It is based on stdio, which is
+            # impossible to combine with select (unless forcing no
+            # buffering).
+            if self.universal_newlines and hasattr(file, 'newlines'):
+                if stdout:
+                    stdout = self._translate_newlines(stdout)
+                if stderr:
+                    stderr = self._translate_newlines(stderr)
+
+            self.wait()
+            return (stdout, stderr)
+
+        def send_signal(self, sig):
+            """Send a signal to the process
+            """
+            if sig == signal.SIGTERM:
+                self.terminate()
+            elif sig == signal.CTRL_C_EVENT:
+                os.kill(self.pid, signal.CTRL_C_EVENT)
+            elif sig == signal.CTRL_BREAK_EVENT:
+                os.kill(self.pid, signal.CTRL_BREAK_EVENT)
+            else:
+                raise ValueError("Unsupported signal: {}".format(sig))
+
+        def terminate(self):
+            """Terminates the process
+            """
+            _subprocess.TerminateProcess(self._handle, 1)
+
+        kill = terminate
+
+    else:
+        #
+        # POSIX methods
+        #
+        def _get_handles(self, stdin, stdout, stderr):
+            """Construct and return tuple with IO objects:
+            p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
+            """
+            p2cread, p2cwrite = None, None
+            c2pread, c2pwrite = None, None
+            errread, errwrite = None, None
+
+            if stdin is None:
+                pass
+            elif stdin == PIPE:
+                p2cread, p2cwrite = self.pipe_cloexec()
+            elif isinstance(stdin, int):
+                p2cread = stdin
+            else:
+                # Assuming file-like object
+                p2cread = stdin.fileno()
+
+            if stdout is None:
+                pass
+            elif stdout == PIPE:
+                c2pread, c2pwrite = self.pipe_cloexec()
+            elif isinstance(stdout, int):
+                c2pwrite = stdout
+            else:
+                # Assuming file-like object
+                c2pwrite = stdout.fileno()
+
+            if stderr is None:
+                pass
+            elif stderr == PIPE:
+                errread, errwrite = self.pipe_cloexec()
+            elif stderr == STDOUT:
+                errwrite = c2pwrite
+            elif isinstance(stderr, int):
+                errwrite = stderr
+            else:
+                # Assuming file-like object
+                errwrite = stderr.fileno()
+
+            return (p2cread, p2cwrite,
+                    c2pread, c2pwrite,
+                    errread, errwrite)
+
+
+        def _set_cloexec_flag(self, fd, cloexec=True):
+            try:
+                cloexec_flag = fcntl.FD_CLOEXEC
+            except AttributeError:
+                cloexec_flag = 1
+
+            old = fcntl.fcntl(fd, fcntl.F_GETFD)
+            if cloexec:
+                fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag)
+            else:
+                fcntl.fcntl(fd, fcntl.F_SETFD, old & ~cloexec_flag)
+
+
+        def pipe_cloexec(self):
+            """Create a pipe with FDs set CLOEXEC."""
+            # Pipes' FDs are set CLOEXEC by default because we don't want them
+            # to be inherited by other subprocesses: the CLOEXEC flag is removed
+            # from the child's FDs by _dup2(), between fork() and exec().
+            # This is not atomic: we would need the pipe2() syscall for that.
+            r, w = os.pipe()
+            self._set_cloexec_flag(r)
+            self._set_cloexec_flag(w)
+            return r, w
+
+
+        def _close_fds(self, but):
+            if hasattr(os, 'closerange'):
+                os.closerange(3, but)
+                os.closerange(but + 1, MAXFD)
+            else:
+                for i in xrange(3, MAXFD):
+                    if i == but:
+                        continue
+                    try:
+                        os.close(i)
+                    except:
+                        pass
+
+
+        def _execute_child(self, args, executable, preexec_fn, close_fds,
+                           cwd, env, universal_newlines,
+                           startupinfo, creationflags, shell,
+                           p2cread, p2cwrite,
+                           c2pread, c2pwrite,
+                           errread, errwrite):
+            """Execute program (POSIX version)"""
+
+            if isinstance(args, types.StringTypes):
+                args = [args]
+            else:
+                args = list(args)
+
+            if shell:
+                args = ["/bin/sh", "-c"] + args
+                if executable:
+                    args[0] = executable
+
+            if executable is None:
+                executable = args[0]
+
+            # For transferring possible exec failure from child to parent
+            # The first char specifies the exception type: 0 means
+            # OSError, 1 means some other error.
+            errpipe_read, errpipe_write = self.pipe_cloexec()
+            try:
+                try:
+                    gc_was_enabled = gc.isenabled()
+                    # Disable gc to avoid bug where gc -> file_dealloc ->
+                    # write to stderr -> hang.  http://bugs.python.org/issue1336
+                    gc.disable()
+                    try:
+                        self.pid = os.fork()
+                    except:
+                        if gc_was_enabled:
+                            gc.enable()
+                        raise
+                    self._child_created = True
+                    if self.pid == 0:
+                        # Child
+                        try:
+                            # Close parent's pipe ends
+                            if p2cwrite is not None:
+                                os.close(p2cwrite)
+                            if c2pread is not None:
+                                os.close(c2pread)
+                            if errread is not None:
+                                os.close(errread)
+                            os.close(errpipe_read)
+
+                            # When duping fds, if there arises a situation
+                            # where one of the fds is either 0, 1 or 2, it
+                            # is possible that it is overwritten (#12607).
+                            if c2pwrite == 0:
+                                c2pwrite = os.dup(c2pwrite)
+                            if errwrite == 0 or errwrite == 1:
+                                errwrite = os.dup(errwrite)
+
+                            # Dup fds for child
+                            def _dup2(a, b):
+                                # dup2() removes the CLOEXEC flag but
+                                # we must do it ourselves if dup2()
+                                # would be a no-op (issue #10806).
+                                if a == b:
+                                    self._set_cloexec_flag(a, False)
+                                elif a is not None:
+                                    os.dup2(a, b)
+                            _dup2(p2cread, 0)
+                            _dup2(c2pwrite, 1)
+                            _dup2(errwrite, 2)
+
+                            # Close pipe fds.  Make sure we don't close the
+                            # same fd more than once, or standard fds.
+                            closed = { None }
+                            for fd in [p2cread, c2pwrite, errwrite]:
+                                if fd not in closed and fd > 2:
+                                    os.close(fd)
+                                    closed.add(fd)
+
+                            # Close all other fds, if asked for
+                            if close_fds:
+                                self._close_fds(but=errpipe_write)
+
+                            if cwd is not None:
+                                os.chdir(cwd)
+
+                            if preexec_fn:
+                                preexec_fn()
+
+                            if env is None:
+                                os.execvp(executable, args)
+                            else:
+                                os.execvpe(executable, args, env)
+
+                        except:
+                            exc_type, exc_value, tb = sys.exc_info()
+                            # Save the traceback and attach it to the exception object
+                            exc_lines = traceback.format_exception(exc_type,
+                                                                   exc_value,
+                                                                   tb)
+                            exc_value.child_traceback = ''.join(exc_lines)
+                            os.write(errpipe_write, pickle.dumps(exc_value))
+
+                        # This exitcode won't be reported to applications, so it
+                        # really doesn't matter what we return.
+                        os._exit(255)
+
+                    # Parent
+                    if gc_was_enabled:
+                        gc.enable()
+                finally:
+                    # be sure the FD is closed no matter what
+                    os.close(errpipe_write)
+
+                if p2cread is not None and p2cwrite is not None:
+                    os.close(p2cread)
+                if c2pwrite is not None and c2pread is not None:
+                    os.close(c2pwrite)
+                if errwrite is not None and errread is not None:
+                    os.close(errwrite)
+
+                # Wait for exec to fail or succeed; possibly raising exception
+                # Exception limited to 1M
+                data = _eintr_retry_call(os.read, errpipe_read, 1048576)
+            finally:
+                # be sure the FD is closed no matter what
+                os.close(errpipe_read)
+
+            if data != "":
+                try:
+                    _eintr_retry_call(os.waitpid, self.pid, 0)
+                except OSError as e:
+                    if e.errno != errno.ECHILD:
+                        raise
+                child_exception = pickle.loads(data)
+                for fd in (p2cwrite, c2pread, errread):
+                    if fd is not None:
+                        os.close(fd)
+                raise child_exception
+
+
+        def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED,
+                _WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED,
+                _WEXITSTATUS=os.WEXITSTATUS):
+            # This method is called (indirectly) by __del__, so it cannot
+            # refer to anything outside of its local scope."""
+            if _WIFSIGNALED(sts):
+                self.returncode = -_WTERMSIG(sts)
+            elif _WIFEXITED(sts):
+                self.returncode = _WEXITSTATUS(sts)
+            else:
+                # Should never happen
+                raise RuntimeError("Unknown child exit status!")
+
+
+        def _internal_poll(self, _deadstate=None, _waitpid=os.waitpid,
+                _WNOHANG=os.WNOHANG, _os_error=os.error):
+            """Check if child process has terminated.  Returns returncode
+            attribute.
+
+            This method is called by __del__, so it cannot reference anything
+            outside of the local scope (nor can any methods it calls).
+
+            """
+            if self.returncode is None:
+                try:
+                    pid, sts = _waitpid(self.pid, _WNOHANG)
+                    if pid == self.pid:
+                        self._handle_exitstatus(sts)
+                except _os_error:
+                    if _deadstate is not None:
+                        self.returncode = _deadstate
+            return self.returncode
+
+
+        def wait(self):
+            """Wait for child process to terminate.  Returns returncode
+            attribute."""
+            if self.returncode is None:
+                try:
+                    pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
+                except OSError as e:
+                    if e.errno != errno.ECHILD:
+                        raise
+                    # This happens if SIGCLD is set to be ignored or waiting
+                    # for child processes has otherwise been disabled for our
+                    # process.  This child is dead, we can't get the status.
+                    sts = 0
+                self._handle_exitstatus(sts)
+            return self.returncode
+
+
+        def _communicate(self, input):
+            if self.stdin:
+                # Flush stdio buffer.  This might block, if the user has
+                # been writing to .stdin in an uncontrolled fashion.
+                self.stdin.flush()
+                if not input:
+                    self.stdin.close()
+
+            if _has_poll:
+                stdout, stderr = self._communicate_with_poll(input)
+            else:
+                stdout, stderr = self._communicate_with_select(input)
+
+            # All data exchanged.  Translate lists into strings.
+            if stdout is not None:
+                stdout = ''.join(stdout)
+            if stderr is not None:
+                stderr = ''.join(stderr)
+
+            # Translate newlines, if requested.  We cannot let the file
+            # object do the translation: It is based on stdio, which is
+            # impossible to combine with select (unless forcing no
+            # buffering).
+            if self.universal_newlines and hasattr(file, 'newlines'):
+                if stdout:
+                    stdout = self._translate_newlines(stdout)
+                if stderr:
+                    stderr = self._translate_newlines(stderr)
+
+            self.wait()
+            return (stdout, stderr)
+
+
+        def _communicate_with_poll(self, input):
+            stdout = None # Return
+            stderr = None # Return
+            fd2file = {}
+            fd2output = {}
+
+            poller = select.poll()
+            def register_and_append(file_obj, eventmask):
+                poller.register(file_obj.fileno(), eventmask)
+                fd2file[file_obj.fileno()] = file_obj
+
+            def close_unregister_and_remove(fd):
+                poller.unregister(fd)
+                fd2file[fd].close()
+                fd2file.pop(fd)
+
+            if self.stdin and input:
+                register_and_append(self.stdin, select.POLLOUT)
+
+            select_POLLIN_POLLPRI = select.POLLIN | select.POLLPRI
+            if self.stdout:
+                register_and_append(self.stdout, select_POLLIN_POLLPRI)
+                fd2output[self.stdout.fileno()] = stdout = []
+            if self.stderr:
+                register_and_append(self.stderr, select_POLLIN_POLLPRI)
+                fd2output[self.stderr.fileno()] = stderr = []
+
+            input_offset = 0
+            while fd2file:
+                try:
+                    ready = poller.poll()
+                except select.error, e:
+                    if e.args[0] == errno.EINTR:
+                        continue
+                    raise
+
+                for fd, mode in ready:
+                    if mode & select.POLLOUT:
+                        chunk = input[input_offset : input_offset + _PIPE_BUF]
+                        try:
+                            input_offset += os.write(fd, chunk)
+                        except OSError as e:
+                            if e.errno == errno.EPIPE:
+                                close_unregister_and_remove(fd)
+                            else:
+                                raise
+                        else:
+                            if input_offset >= len(input):
+                                close_unregister_and_remove(fd)
+                    elif mode & select_POLLIN_POLLPRI:
+                        data = os.read(fd, 4096)
+                        if not data:
+                            close_unregister_and_remove(fd)
+                        fd2output[fd].append(data)
+                    else:
+                        # Ignore hang up or errors.
+                        close_unregister_and_remove(fd)
+
+            return (stdout, stderr)
+
+
+        def _communicate_with_select(self, input):
+            read_set = []
+            write_set = []
+            stdout = None # Return
+            stderr = None # Return
+
+            if self.stdin and input:
+                write_set.append(self.stdin)
+            if self.stdout:
+                read_set.append(self.stdout)
+                stdout = []
+            if self.stderr:
+                read_set.append(self.stderr)
+                stderr = []
+
+            input_offset = 0
+            while read_set or write_set:
+                try:
+                    rlist, wlist, xlist = select.select(read_set, write_set, [])
+                except select.error, e:
+                    if e.args[0] == errno.EINTR:
+                        continue
+                    raise
+
+                if self.stdin in wlist:
+                    chunk = input[input_offset : input_offset + _PIPE_BUF]
+                    try:
+                        bytes_written = os.write(self.stdin.fileno(), chunk)
+                    except OSError as e:
+                        if e.errno == errno.EPIPE:
+                            self.stdin.close()
+                            write_set.remove(self.stdin)
+                        else:
+                            raise
+                    else:
+                        input_offset += bytes_written
+                        if input_offset >= len(input):
+                            self.stdin.close()
+                            write_set.remove(self.stdin)
+
+                if self.stdout in rlist:
+                    data = os.read(self.stdout.fileno(), 1024)
+                    if data == "":
+                        self.stdout.close()
+                        read_set.remove(self.stdout)
+                    stdout.append(data)
+
+                if self.stderr in rlist:
+                    data = os.read(self.stderr.fileno(), 1024)
+                    if data == "":
+                        self.stderr.close()
+                        read_set.remove(self.stderr)
+                    stderr.append(data)
+
+            return (stdout, stderr)
+
+
+        def send_signal(self, sig):
+            """Send a signal to the process
+            """
+            os.kill(self.pid, sig)
+
+        def terminate(self):
+            """Terminate the process with SIGTERM
+            """
+            self.send_signal(signal.SIGTERM)
+
+        def kill(self):
+            """Kill the process with SIGKILL
+            """
+            self.send_signal(signal.SIGKILL)
+
+
+def _demo_posix():
+    #
+    # Example 1: Simple redirection: Get process list
+    #
+    plist = Popen(["ps"], stdout=PIPE).communicate()[0]
+    print "Process list:"
+    print plist
+
+    #
+    # Example 2: Change uid before executing child
+    #
+    if os.getuid() == 0:
+        p = Popen(["id"], preexec_fn=lambda: os.setuid(100))
+        p.wait()
+
+    #
+    # Example 3: Connecting several subprocesses
+    #
+    print "Looking for 'hda'..."
+    p1 = Popen(["dmesg"], stdout=PIPE)
+    p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
+    print repr(p2.communicate()[0])
+
+    #
+    # Example 4: Catch execution error
+    #
+    print
+    print "Trying a weird file..."
+    try:
+        print Popen(["/this/path/does/not/exist"]).communicate()
+    except OSError, e:
+        if e.errno == errno.ENOENT:
+            print "The file didn't exist.  I thought so..."
+            print "Child traceback:"
+            print e.child_traceback
+        else:
+            print "Error", e.errno
+    else:
+        print >>sys.stderr, "Gosh.  No error."
+
+
+def _demo_windows():
+    #
+    # Example 1: Connecting several subprocesses
+    #
+    print "Looking for 'PROMPT' in set output..."
+    p1 = Popen("set", stdout=PIPE, shell=True)
+    p2 = Popen('find "PROMPT"', stdin=p1.stdout, stdout=PIPE)
+    print repr(p2.communicate()[0])
+
+    #
+    # Example 2: Simple execution of program
+    #
+    print "Executing calc..."
+    p = Popen("calc")
+    p.wait()
+
+
+if __name__ == "__main__":
+    if mswindows:
+        _demo_windows()
+    else:
+        _demo_posix()

cherrypy/_cperror.py

         response.headers['Content-Type'] = "text/html;charset=utf-8"
         response.headers.pop('Content-Length', None)
 
-        content = ntob(self.get_error_page(self.status, traceback=tb,
-                                           message=self._message), 'utf-8')
+        content = self.get_error_page(self.status, traceback=tb,
+            message=self._message).encode('utf-8')
         response.body = content
 
         _be_ie_unfriendly(self.code)

cherrypy/test/helper.py

 
 import cherrypy
 from cherrypy._cpcompat import basestring, copyitems, HTTPSConnection, ntob
+from cherrypy._cpcompat import subprocess
 from cherrypy.lib import httputil
 from cherrypy.lib import gctools
 from cherrypy.lib.reprconf import unrepr
         """Start cherryd in a subprocess."""
         cherrypy._cpserver.wait_for_free_port(self.host, self.port)
 
-        args = [sys.executable, os.path.join(thisdir, '..', 'cherryd'),
-                '-c', self.config_file, '-p', self.pid_file]
+        args = [
+            os.path.join(thisdir, '..', 'cherryd'),
+            '-c', self.config_file,
+            '-p', self.pid_file,
+        ]
 
         if not isinstance(imports, (list, tuple)):
             imports = [imports]
             env['PYTHONPATH'] = os.pathsep.join((grandparentdir, env['PYTHONPATH']))
         else:
             env['PYTHONPATH'] = grandparentdir
+        self._proc = subprocess.Popen([sys.executable] + args, env=env)
         if self.wait:
-            self.exit_code = os.spawnve(os.P_WAIT, sys.executable, args, env)
+            self.exit_code = self._proc.wait()
         else:
-            os.spawnve(os.P_NOWAIT, sys.executable, args, env)
             cherrypy._cpserver.wait_for_occupied_port(self.host, self.port)
 
         # Give the engine a wee bit more time to finish STARTING
             time.sleep(1)
 
     def get_pid(self):
-        return int(open(self.pid_file, 'rb').read())
+        return self._proc.pid
 
     def join(self):
         """Wait for the process to exit."""
-        try:
-            try:
-                # Mac, UNIX
-                os.wait()
-            except AttributeError:
-                # Windows
-                try:
-                    pid = self.get_pid()
-                except IOError:
-                    # Assume the subprocess deleted the pidfile on shutdown.
-                    pass
-                else:
-                    os.waitpid(pid, 0)
-        except OSError:
-            x = sys.exc_info()[1]
-            if x.args != (10, 'No child processes'):
-                raise
-
+        self._proc.wait()

cherrypy/test/test_states.py

 
 import cherrypy
 import cherrypy.process.servers
+from cherrypy.test import helper
 
 engine = cherrypy.engine
 thisdir = os.path.join(os.getcwd(), os.path.dirname(__file__))
 
     db_connection.subscribe()
 
-
-
 # ------------ Enough helpers. Time for real live test cases. ------------ #
 
-
-from cherrypy.test import helper
-
 class ServerStateTests(helper.CPWebCase):
     setup_server = staticmethod(setup_server)
 
     def test_4_Autoreload(self):
         # Start the demo script in a new process
         p = helper.CPProcess(ssl=(self.scheme.lower()=='https'))
-        p.write_conf(
-                extra='test_case_name: "test_4_Autoreload"')
+        p.write_conf(extra='test_case_name: "test_4_Autoreload"')
         p.start(imports='cherrypy.test._test_states_demo')
         try:
             self.getPage("/start")

cherrypy/test/test_tutorials.py

             </body>
             </html>
         '''
+        # the tutorial has some annoying spaces in otherwise blank lines
+        msg = msg.replace('</h2>\n\n', '</h2>\n        \n')
+        msg = msg.replace('</p>\n\n', '</p>\n        \n')
         self.getPage("/another/")
         self.assertBody(msg)
 

cherrypy/test/webtest.py

                 conn.putrequest(method.upper(), url)
 
             for key, value in headers:
-                conn.putheader(key, ntob(value, "Latin-1"))
+                conn.putheader(key, value.encode("Latin-1"))
             conn.endheaders()
 
             if body is not None:
Tip: Filter by directory path e.g. /media app.js to search for public/media/app.js.
Tip: Use camelCasing e.g. ProjME to search for ProjectModifiedEvent.java.
Tip: Filter by extension type e.g. /repo .js to search for all .js files in the /repo directory.
Tip: Separate your search with spaces e.g. /ssh pom.xml to search for src/ssh/pom.xml.
Tip: Use ↑ and ↓ arrow keys to navigate and return to view the file.
Tip: You can also navigate files with Ctrl+j (next) and Ctrl+k (previous) and view the file with Ctrl+o.
Tip: You can also navigate files with Alt+j (next) and Alt+k (previous) and view the file with Alt+o.