Python code coverage for Lib/subprocess.py

#	count	content
1	n/a	# subprocess - Subprocesses with accessible I/O streams
2	n/a	#
3	n/a	# For more information about this module, see PEP 324.
4	n/a	#
5	n/a	# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
6	n/a	#
7	n/a	# Licensed to PSF under a Contributor Agreement.
8	n/a	# See http://www.python.org/2.4/license for licensing details.
9	n/a
10	n/a	r"""subprocess - Subprocesses with accessible I/O streams
11	n/a
12	n/a	This module allows you to spawn processes, connect to their
13	n/a	input/output/error pipes, and obtain their return codes. This module
14	n/a	intends to replace several other, older modules and functions, like:
15	n/a
16	n/a	os.system
17	n/a	os.spawn*
18	n/a
19	n/a	Information about how the subprocess module can be used to replace these
20	n/a	modules and functions can be found below.
21	n/a
22	n/a
23	n/a
24	n/a	Using the subprocess module
25	n/a	===========================
26	n/a	This module defines one class called Popen:
27	n/a
28	n/a	class Popen(args, bufsize=0, executable=None,
29	n/a	stdin=None, stdout=None, stderr=None,
30	n/a	preexec_fn=None, close_fds=False, shell=False,
31	n/a	cwd=None, env=None, universal_newlines=False,
32	n/a	startupinfo=None, creationflags=0,
33	n/a	restore_signals=True, start_new_session=False):
34	n/a
35	n/a
36	n/a	Arguments are:
37	n/a
38	n/a	args should be a string, or a sequence of program arguments. The
39	n/a	program to execute is normally the first item in the args sequence or
40	n/a	string, but can be explicitly set by using the executable argument.
41	n/a
42	n/a	On UNIX, with shell=False (default): In this case, the Popen class
43	n/a	uses os.execvp() to execute the child program. args should normally
44	n/a	be a sequence. A string will be treated as a sequence with the string
45	n/a	as the only item (the program to execute).
46	n/a
47	n/a	On UNIX, with shell=True: If args is a string, it specifies the
48	n/a	command string to execute through the shell. If args is a sequence,
49	n/a	the first item specifies the command string, and any additional items
50	n/a	will be treated as additional shell arguments.
51	n/a
52	n/a	On Windows: the Popen class uses CreateProcess() to execute the child
53	n/a	program, which operates on strings. If args is a sequence, it will be
54	n/a	converted to a string using the list2cmdline method. Please note that
55	n/a	not all MS Windows applications interpret the command line the same
56	n/a	way: The list2cmdline is designed for applications using the same
57	n/a	rules as the MS C runtime.
58	n/a
59	n/a	bufsize, if given, has the same meaning as the corresponding argument
60	n/a	to the built-in open() function: 0 means unbuffered, 1 means line
61	n/a	buffered, any other positive value means use a buffer of
62	n/a	(approximately) that size. A negative bufsize means to use the system
63	n/a	default, which usually means fully buffered. The default value for
64	n/a	bufsize is 0 (unbuffered).
65	n/a
66	n/a	stdin, stdout and stderr specify the executed programs' standard
67	n/a	input, standard output and standard error file handles, respectively.
68	n/a	Valid values are PIPE, an existing file descriptor (a positive
69	n/a	integer), an existing file object, and None. PIPE indicates that a
70	n/a	new pipe to the child should be created. With None, no redirection
71	n/a	will occur; the child's file handles will be inherited from the
72	n/a	parent. Additionally, stderr can be STDOUT, which indicates that the
73	n/a	stderr data from the applications should be captured into the same
74	n/a	file handle as for stdout.
75	n/a
76	n/a	On UNIX, if preexec_fn is set to a callable object, this object will be
77	n/a	called in the child process just before the child is executed. The use
78	n/a	of preexec_fn is not thread safe, using it in the presence of threads
79	n/a	could lead to a deadlock in the child process before the new executable
80	n/a	is executed.
81	n/a
82	n/a	If close_fds is true, all file descriptors except 0, 1 and 2 will be
83	n/a	closed before the child process is executed.
84	n/a
85	n/a	if shell is true, the specified command will be executed through the
86	n/a	shell.
87	n/a
88	n/a	If cwd is not None, the current directory will be changed to cwd
89	n/a	before the child is executed.
90	n/a
91	n/a	On UNIX, if restore_signals is True all signals that Python sets to
92	n/a	SIG_IGN are restored to SIG_DFL in the child process before the exec.
93	n/a	Currently this includes the SIGPIPE, SIGXFZ and SIGXFSZ signals. This
94	n/a	parameter does nothing on Windows.
95	n/a
96	n/a	On UNIX, if start_new_session is True, the setsid() system call will be made
97	n/a	in the child process prior to executing the command.
98	n/a
99	n/a	If env is not None, it defines the environment variables for the new
100	n/a	process.
101	n/a
102	n/a	If universal_newlines is true, the file objects stdout and stderr are
103	n/a	opened as a text files, but lines may be terminated by any of '\n',
104	n/a	the Unix end-of-line convention, '\r', the Macintosh convention or
105	n/a	'\r\n', the Windows convention. All of these external representations
106	n/a	are seen as '\n' by the Python program. Note: This feature is only
107	n/a	available if Python is built with universal newline support (the
108	n/a	default). Also, the newlines attribute of the file objects stdout,
109	n/a	stdin and stderr are not updated by the communicate() method.
110	n/a
111	n/a	The startupinfo and creationflags, if given, will be passed to the
112	n/a	underlying CreateProcess() function. They can specify things such as
113	n/a	appearance of the main window and priority for the new process.
114	n/a	(Windows only)
115	n/a
116	n/a
117	n/a	This module also defines some shortcut functions:
118	n/a
119	n/a	call(popenargs, *kwargs):
120	n/a	Run command with arguments. Wait for command to complete, then
121	n/a	return the returncode attribute.
122	n/a
123	n/a	The arguments are the same as for the Popen constructor. Example:
124	n/a
125	n/a	>>> retcode = subprocess.call(["ls", "-l"])
126	n/a
127	n/a	check_call(popenargs, *kwargs):
128	n/a	Run command with arguments. Wait for command to complete. If the
129	n/a	exit code was zero then return, otherwise raise
130	n/a	CalledProcessError. The CalledProcessError object will have the
131	n/a	return code in the returncode attribute.
132	n/a
133	n/a	The arguments are the same as for the Popen constructor. Example:
134	n/a
135	n/a	>>> subprocess.check_call(["ls", "-l"])
136	n/a	0
137	n/a
138	n/a	getstatusoutput(cmd):
139	n/a	Return (status, output) of executing cmd in a shell.
140	n/a
141	n/a	Execute the string 'cmd' in a shell with os.popen() and return a 2-tuple
142	n/a	(status, output). cmd is actually run as '{ cmd ; } 2>&1', so that the
143	n/a	returned output will contain output or error messages. A trailing newline
144	n/a	is stripped from the output. The exit status for the command can be
145	n/a	interpreted according to the rules for the C function wait(). Example:
146	n/a
147	n/a	>>> subprocess.getstatusoutput('ls /bin/ls')
148	n/a	(0, '/bin/ls')
149	n/a	>>> subprocess.getstatusoutput('cat /bin/junk')
150	n/a	(256, 'cat: /bin/junk: No such file or directory')
151	n/a	>>> subprocess.getstatusoutput('/bin/junk')
152	n/a	(256, 'sh: /bin/junk: not found')
153	n/a
154	n/a	getoutput(cmd):
155	n/a	Return output (stdout or stderr) of executing cmd in a shell.
156	n/a
157	n/a	Like getstatusoutput(), except the exit status is ignored and the return
158	n/a	value is a string containing the command's output. Example:
159	n/a
160	n/a	>>> subprocess.getoutput('ls /bin/ls')
161	n/a	'/bin/ls'
162	n/a
163	n/a	check_output(popenargs, *kwargs):
164	n/a	Run command with arguments and return its output as a byte string.
165	n/a
166	n/a	If the exit code was non-zero it raises a CalledProcessError. The
167	n/a	CalledProcessError object will have the return code in the returncode
168	n/a	attribute and output in the output attribute.
169	n/a
170	n/a	The arguments are the same as for the Popen constructor. Example:
171	n/a
172	n/a	>>> output = subprocess.check_output(["ls", "-l", "/dev/null"])
173	n/a
174	n/a
175	n/a	Exceptions
176	n/a	----------
177	n/a	Exceptions raised in the child process, before the new program has
178	n/a	started to execute, will be re-raised in the parent. Additionally,
179	n/a	the exception object will have one extra attribute called
180	n/a	'child_traceback', which is a string containing traceback information
181	n/a	from the childs point of view.
182	n/a
183	n/a	The most common exception raised is OSError. This occurs, for
184	n/a	example, when trying to execute a non-existent file. Applications
185	n/a	should prepare for OSErrors.
186	n/a
187	n/a	A ValueError will be raised if Popen is called with invalid arguments.
188	n/a
189	n/a	check_call() and check_output() will raise CalledProcessError, if the
190	n/a	called process returns a non-zero return code.
191	n/a
192	n/a
193	n/a	Security
194	n/a	--------
195	n/a	Unlike some other popen functions, this implementation will never call
196	n/a	/bin/sh implicitly. This means that all characters, including shell
197	n/a	metacharacters, can safely be passed to child processes.
198	n/a
199	n/a
200	n/a	Popen objects
201	n/a	=============
202	n/a	Instances of the Popen class have the following methods:
203	n/a
204	n/a	poll()
205	n/a	Check if child process has terminated. Returns returncode
206	n/a	attribute.
207	n/a
208	n/a	wait()
209	n/a	Wait for child process to terminate. Returns returncode attribute.
210	n/a
211	n/a	communicate(input=None)
212	n/a	Interact with process: Send data to stdin. Read data from stdout
213	n/a	and stderr, until end-of-file is reached. Wait for process to
214	n/a	terminate. The optional input argument should be a string to be
215	n/a	sent to the child process, or None, if no data should be sent to
216	n/a	the child.
217	n/a
218	n/a	communicate() returns a tuple (stdout, stderr).
219	n/a
220	n/a	Note: The data read is buffered in memory, so do not use this
221	n/a	method if the data size is large or unlimited.
222	n/a
223	n/a	The following attributes are also available:
224	n/a
225	n/a	stdin
226	n/a	If the stdin argument is PIPE, this attribute is a file object
227	n/a	that provides input to the child process. Otherwise, it is None.
228	n/a
229	n/a	stdout
230	n/a	If the stdout argument is PIPE, this attribute is a file object
231	n/a	that provides output from the child process. Otherwise, it is
232	n/a	None.
233	n/a
234	n/a	stderr
235	n/a	If the stderr argument is PIPE, this attribute is file object that
236	n/a	provides error output from the child process. Otherwise, it is
237	n/a	None.
238	n/a
239	n/a	pid
240	n/a	The process ID of the child process.
241	n/a
242	n/a	returncode
243	n/a	The child return code. A None value indicates that the process
244	n/a	hasn't terminated yet. A negative value -N indicates that the
245	n/a	child was terminated by signal N (UNIX only).
246	n/a
247	n/a
248	n/a	Replacing older functions with the subprocess module
249	n/a	====================================================
250	n/a	In this section, "a ==> b" means that b can be used as a replacement
251	n/a	for a.
252	n/a
253	n/a	Note: All functions in this section fail (more or less) silently if
254	n/a	the executed program cannot be found; this module raises an OSError
255	n/a	exception.
256	n/a
257	n/a	In the following examples, we assume that the subprocess module is
258	n/a	imported with "from subprocess import *".
259	n/a
260	n/a
261	n/a	Replacing /bin/sh shell backquote
262	n/a	---------------------------------
263	n/a	output=`mycmd myarg`
264	n/a	==>
265	n/a	output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0]
266	n/a
267	n/a
268	n/a	Replacing shell pipe line
269	n/a	-------------------------
270	n/a	output=`dmesg \| grep hda`
271	n/a	==>
272	n/a	p1 = Popen(["dmesg"], stdout=PIPE)
273	n/a	p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
274	n/a	output = p2.communicate()[0]
275	n/a
276	n/a
277	n/a	Replacing os.system()
278	n/a	---------------------
279	n/a	sts = os.system("mycmd" + " myarg")
280	n/a	==>
281	n/a	p = Popen("mycmd" + " myarg", shell=True)
282	n/a	pid, sts = os.waitpid(p.pid, 0)
283	n/a
284	n/a	Note:
285	n/a
286	n/a	* Calling the program through the shell is usually not required.
287	n/a
288	n/a	* It's easier to look at the returncode attribute than the
289	n/a	exitstatus.
290	n/a
291	n/a	A more real-world example would look like this:
292	n/a
293	n/a	try:
294	n/a	retcode = call("mycmd" + " myarg", shell=True)
295	n/a	if retcode < 0:
296	n/a	print("Child was terminated by signal", -retcode, file=sys.stderr)
297	n/a	else:
298	n/a	print("Child returned", retcode, file=sys.stderr)
299	n/a	except OSError as e:
300	n/a	print("Execution failed:", e, file=sys.stderr)
301	n/a
302	n/a
303	n/a	Replacing os.spawn*
304	n/a	-------------------
305	n/a	P_NOWAIT example:
306	n/a
307	n/a	pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg")
308	n/a	==>
309	n/a	pid = Popen(["/bin/mycmd", "myarg"]).pid
310	n/a
311	n/a
312	n/a	P_WAIT example:
313	n/a
314	n/a	retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg")
315	n/a	==>
316	n/a	retcode = call(["/bin/mycmd", "myarg"])
317	n/a
318	n/a
319	n/a	Vector example:
320	n/a
321	n/a	os.spawnvp(os.P_NOWAIT, path, args)
322	n/a	==>
323	n/a	Popen([path] + args[1:])
324	n/a
325	n/a
326	n/a	Environment example:
327	n/a
328	n/a	os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env)
329	n/a	==>
330	n/a	Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"})
331	n/a	"""
332	n/a
333	n/a	import sys
334	n/a	mswindows = (sys.platform == "win32")
335	n/a
336	n/a	import io
337	n/a	import os
338	n/a	import traceback
339	n/a	import gc
340	n/a	import signal
341	n/a	import builtins
342	n/a
343	n/a	# Exception classes used by this module.
344	n/a	class CalledProcessError(Exception):
345	n/a	"""This exception is raised when a process run by check_call() or
346	n/a	check_output() returns a non-zero exit status.
347	n/a	The exit status will be stored in the returncode attribute;
348	n/a	check_output() will also store the output in the output attribute.
349	n/a	"""
350	n/a	def __init__(self, returncode, cmd, output=None):
351	n/a	self.returncode = returncode
352	n/a	self.cmd = cmd
353	n/a	self.output = output
354	n/a	def __str__(self):
355	n/a	return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
356	n/a
357	n/a
358	n/a	if mswindows:
359	n/a	import threading
360	n/a	import msvcrt
361	n/a	import _subprocess
362	n/a	class STARTUPINFO:
363	n/a	dwFlags = 0
364	n/a	hStdInput = None
365	n/a	hStdOutput = None
366	n/a	hStdError = None
367	n/a	wShowWindow = 0
368	n/a	class pywintypes:
369	n/a	error = IOError
370	n/a	else:
371	n/a	import select
372	n/a	_has_poll = hasattr(select, 'poll')
373	n/a	import errno
374	n/a	import fcntl
375	n/a	import pickle
376	n/a
377	n/a	try:
378	n/a	import _posixsubprocess
379	n/a	except ImportError:
380	n/a	_posixsubprocess = None
381	n/a	import warnings
382	n/a	warnings.warn("The _posixsubprocess module is not being used. "
383	n/a	"Child process reliability may suffer if your "
384	n/a	"program uses threads.", RuntimeWarning)
385	n/a
386	n/a	# When select or poll has indicated that the file is writable,
387	n/a	# we can write up to _PIPE_BUF bytes without risk of blocking.
388	n/a	# POSIX defines PIPE_BUF as >= 512.
389	n/a	_PIPE_BUF = getattr(select, 'PIPE_BUF', 512)
390	n/a
391	n/a
392	n/a	__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call", "getstatusoutput",
393	n/a	"getoutput", "check_output", "CalledProcessError"]
394	n/a
395	n/a	if mswindows:
396	n/a	from _subprocess import CREATE_NEW_CONSOLE, CREATE_NEW_PROCESS_GROUP
397	n/a	__all__.extend(["CREATE_NEW_CONSOLE", "CREATE_NEW_PROCESS_GROUP"])
398	n/a	try:
399	n/a	MAXFD = os.sysconf("SC_OPEN_MAX")
400	n/a	except:
401	n/a	MAXFD = 256
402	n/a
403	n/a	_active = []
404	n/a
405	n/a	def _cleanup():
406	n/a	for inst in _active[:]:
407	n/a	res = inst._internal_poll(_deadstate=sys.maxsize)
408	n/a	if res is not None and res >= 0:
409	n/a	try:
410	n/a	_active.remove(inst)
411	n/a	except ValueError:
412	n/a	# This can happen if two threads create a new Popen instance.
413	n/a	# It's harmless that it was already removed, so ignore.
414	n/a	pass
415	n/a
416	n/a	PIPE = -1
417	n/a	STDOUT = -2
418	n/a
419	n/a
420	n/a	def _eintr_retry_call(func, *args):
421	n/a	while True:
422	n/a	try:
423	n/a	return func(*args)
424	n/a	except OSError as e:
425	n/a	if e.errno == errno.EINTR:
426	n/a	continue
427	n/a	raise
428	n/a
429	n/a
430	n/a	def call(popenargs, *kwargs):
431	n/a	"""Run command with arguments. Wait for command to complete, then
432	n/a	return the returncode attribute.
433	n/a
434	n/a	The arguments are the same as for the Popen constructor. Example:
435	n/a
436	n/a	retcode = call(["ls", "-l"])
437	n/a	"""
438	n/a	return Popen(popenargs, *kwargs).wait()
439	n/a
440	n/a
441	n/a	def check_call(popenargs, *kwargs):
442	n/a	"""Run command with arguments. Wait for command to complete. If
443	n/a	the exit code was zero then return, otherwise raise
444	n/a	CalledProcessError. The CalledProcessError object will have the
445	n/a	return code in the returncode attribute.
446	n/a
447	n/a	The arguments are the same as for the Popen constructor. Example:
448	n/a
449	n/a	check_call(["ls", "-l"])
450	n/a	"""
451	n/a	retcode = call(popenargs, *kwargs)
452	n/a	if retcode:
453	n/a	cmd = kwargs.get("args")
454	n/a	if cmd is None:
455	n/a	cmd = popenargs[0]
456	n/a	raise CalledProcessError(retcode, cmd)
457	n/a	return 0
458	n/a
459	n/a
460	n/a	def check_output(popenargs, *kwargs):
461	n/a	r"""Run command with arguments and return its output as a byte string.
462	n/a
463	n/a	If the exit code was non-zero it raises a CalledProcessError. The
464	n/a	CalledProcessError object will have the return code in the returncode
465	n/a	attribute and output in the output attribute.
466	n/a
467	n/a	The arguments are the same as for the Popen constructor. Example:
468	n/a
469	n/a	>>> check_output(["ls", "-l", "/dev/null"])
470	n/a	b'crw-rw-rw- 1 root root 1, 3 Oct 18 2007 /dev/null\n'
471	n/a
472	n/a	The stdout argument is not allowed as it is used internally.
473	n/a	To capture standard error in the result, use stderr=STDOUT.
474	n/a
475	n/a	>>> check_output(["/bin/sh", "-c",
476	n/a	... "ls -l non_existent_file ; exit 0"],
477	n/a	... stderr=STDOUT)
478	n/a	b'ls: non_existent_file: No such file or directory\n'
479	n/a	"""
480	n/a	if 'stdout' in kwargs:
481	n/a	raise ValueError('stdout argument not allowed, it will be overridden.')
482	n/a	process = Popen(popenargs, stdout=PIPE, *kwargs)
483	n/a	output, unused_err = process.communicate()
484	n/a	retcode = process.poll()
485	n/a	if retcode:
486	n/a	cmd = kwargs.get("args")
487	n/a	if cmd is None:
488	n/a	cmd = popenargs[0]
489	n/a	raise CalledProcessError(retcode, cmd, output=output)
490	n/a	return output
491	n/a
492	n/a
493	n/a	def list2cmdline(seq):
494	n/a	"""
495	n/a	Translate a sequence of arguments into a command line
496	n/a	string, using the same rules as the MS C runtime:
497	n/a
498	n/a	1) Arguments are delimited by white space, which is either a
499	n/a	space or a tab.
500	n/a
501	n/a	2) A string surrounded by double quotation marks is
502	n/a	interpreted as a single argument, regardless of white space
503	n/a	contained within. A quoted string can be embedded in an
504	n/a	argument.
505	n/a
506	n/a	3) A double quotation mark preceded by a backslash is
507	n/a	interpreted as a literal double quotation mark.
508	n/a
509	n/a	4) Backslashes are interpreted literally, unless they
510	n/a	immediately precede a double quotation mark.
511	n/a
512	n/a	5) If backslashes immediately precede a double quotation mark,
513	n/a	every pair of backslashes is interpreted as a literal
514	n/a	backslash. If the number of backslashes is odd, the last
515	n/a	backslash escapes the next double quotation mark as
516	n/a	described in rule 3.
517	n/a	"""
518	n/a
519	n/a	# See
520	n/a	# http://msdn.microsoft.com/en-us/library/17w5ykft.aspx
521	n/a	# or search http://msdn.microsoft.com for
522	n/a	# "Parsing C++ Command-Line Arguments"
523	n/a	result = []
524	n/a	needquote = False
525	n/a	for arg in seq:
526	n/a	bs_buf = []
527	n/a
528	n/a	# Add a space to separate this argument from the others
529	n/a	if result:
530	n/a	result.append(' ')
531	n/a
532	n/a	needquote = (" " in arg) or ("\t" in arg) or not arg
533	n/a	if needquote:
534	n/a	result.append('"')
535	n/a
536	n/a	for c in arg:
537	n/a	if c == '\\':
538	n/a	# Don't know if we need to double yet.
539	n/a	bs_buf.append(c)
540	n/a	elif c == '"':
541	n/a	# Double backslashes.
542	n/a	result.append('\\' * len(bs_buf)*2)
543	n/a	bs_buf = []
544	n/a	result.append('\\"')
545	n/a	else:
546	n/a	# Normal char
547	n/a	if bs_buf:
548	n/a	result.extend(bs_buf)
549	n/a	bs_buf = []
550	n/a	result.append(c)
551	n/a
552	n/a	# Add remaining backslashes, if any.
553	n/a	if bs_buf:
554	n/a	result.extend(bs_buf)
555	n/a
556	n/a	if needquote:
557	n/a	result.extend(bs_buf)
558	n/a	result.append('"')
559	n/a
560	n/a	return ''.join(result)
561	n/a
562	n/a
563	n/a	# Various tools for executing commands and looking at their output and status.
564	n/a	#
565	n/a	# NB This only works (and is only relevant) for UNIX.
566	n/a
567	n/a	def getstatusoutput(cmd):
568	n/a	"""Return (status, output) of executing cmd in a shell.
569	n/a
570	n/a	Execute the string 'cmd' in a shell with os.popen() and return a 2-tuple
571	n/a	(status, output). cmd is actually run as '{ cmd ; } 2>&1', so that the
572	n/a	returned output will contain output or error messages. A trailing newline
573	n/a	is stripped from the output. The exit status for the command can be
574	n/a	interpreted according to the rules for the C function wait(). Example:
575	n/a
576	n/a	>>> import subprocess
577	n/a	>>> subprocess.getstatusoutput('ls /bin/ls')
578	n/a	(0, '/bin/ls')
579	n/a	>>> subprocess.getstatusoutput('cat /bin/junk')
580	n/a	(256, 'cat: /bin/junk: No such file or directory')
581	n/a	>>> subprocess.getstatusoutput('/bin/junk')
582	n/a	(256, 'sh: /bin/junk: not found')
583	n/a	"""
584	n/a	pipe = os.popen('{ ' + cmd + '; } 2>&1', 'r')
585	n/a	text = pipe.read()
586	n/a	sts = pipe.close()
587	n/a	if sts is None: sts = 0
588	n/a	if text[-1:] == '\n': text = text[:-1]
589	n/a	return sts, text
590	n/a
591	n/a
592	n/a	def getoutput(cmd):
593	n/a	"""Return output (stdout or stderr) of executing cmd in a shell.
594	n/a
595	n/a	Like getstatusoutput(), except the exit status is ignored and the return
596	n/a	value is a string containing the command's output. Example:
597	n/a
598	n/a	>>> import subprocess
599	n/a	>>> subprocess.getoutput('ls /bin/ls')
600	n/a	'/bin/ls'
601	n/a	"""
602	n/a	return getstatusoutput(cmd)[1]
603	n/a
604	n/a
605	n/a	class Popen(object):
606	n/a	def __init__(self, args, bufsize=0, executable=None,
607	n/a	stdin=None, stdout=None, stderr=None,
608	n/a	preexec_fn=None, close_fds=False, shell=False,
609	n/a	cwd=None, env=None, universal_newlines=False,
610	n/a	startupinfo=None, creationflags=0,
611	n/a	restore_signals=True, start_new_session=False):
612	n/a	"""Create new Popen instance."""
613	n/a	_cleanup()
614	n/a
615	n/a	self._child_created = False
616	n/a	if bufsize is None:
617	n/a	bufsize = 0 # Restore default
618	n/a	if not isinstance(bufsize, int):
619	n/a	raise TypeError("bufsize must be an integer")
620	n/a
621	n/a	if mswindows:
622	n/a	if preexec_fn is not None:
623	n/a	raise ValueError("preexec_fn is not supported on Windows "
624	n/a	"platforms")
625	n/a	if close_fds and (stdin is not None or stdout is not None or
626	n/a	stderr is not None):
627	n/a	raise ValueError("close_fds is not supported on Windows "
628	n/a	"platforms if you redirect stdin/stdout/stderr")
629	n/a	else:
630	n/a	# POSIX
631	n/a	if startupinfo is not None:
632	n/a	raise ValueError("startupinfo is only supported on Windows "
633	n/a	"platforms")
634	n/a	if creationflags != 0:
635	n/a	raise ValueError("creationflags is only supported on Windows "
636	n/a	"platforms")
637	n/a
638	n/a	self.stdin = None
639	n/a	self.stdout = None
640	n/a	self.stderr = None
641	n/a	self.pid = None
642	n/a	self.returncode = None
643	n/a	self.universal_newlines = universal_newlines
644	n/a
645	n/a	# Input and output objects. The general principle is like
646	n/a	# this:
647	n/a	#
648	n/a	# Parent Child
649	n/a	# ------ -----
650	n/a	# p2cwrite ---stdin---> p2cread
651	n/a	# c2pread <--stdout--- c2pwrite
652	n/a	# errread <--stderr--- errwrite
653	n/a	#
654	n/a	# On POSIX, the child objects are file descriptors. On
655	n/a	# Windows, these are Windows file handles. The parent objects
656	n/a	# are file descriptors on both platforms. The parent objects
657	n/a	# are -1 when not using PIPEs. The child objects are -1
658	n/a	# when not redirecting.
659	n/a
660	n/a	(p2cread, p2cwrite,
661	n/a	c2pread, c2pwrite,
662	n/a	errread, errwrite) = self._get_handles(stdin, stdout, stderr)
663	n/a
664	n/a	self._execute_child(args, executable, preexec_fn, close_fds,
665	n/a	cwd, env, universal_newlines,
666	n/a	startupinfo, creationflags, shell,
667	n/a	p2cread, p2cwrite,
668	n/a	c2pread, c2pwrite,
669	n/a	errread, errwrite,
670	n/a	restore_signals, start_new_session)
671	n/a
672	n/a	if mswindows:
673	n/a	if p2cwrite != -1:
674	n/a	p2cwrite = msvcrt.open_osfhandle(p2cwrite.Detach(), 0)
675	n/a	if c2pread != -1:
676	n/a	c2pread = msvcrt.open_osfhandle(c2pread.Detach(), 0)
677	n/a	if errread != -1:
678	n/a	errread = msvcrt.open_osfhandle(errread.Detach(), 0)
679	n/a
680	n/a	if bufsize == 0:
681	n/a	bufsize = 1 # Nearly unbuffered (XXX for now)
682	n/a	if p2cwrite != -1:
683	n/a	self.stdin = io.open(p2cwrite, 'wb', bufsize)
684	n/a	if self.universal_newlines:
685	n/a	self.stdin = io.TextIOWrapper(self.stdin)
686	n/a	if c2pread != -1:
687	n/a	self.stdout = io.open(c2pread, 'rb', bufsize)
688	n/a	if universal_newlines:
689	n/a	self.stdout = io.TextIOWrapper(self.stdout)
690	n/a	if errread != -1:
691	n/a	self.stderr = io.open(errread, 'rb', bufsize)
692	n/a	if universal_newlines:
693	n/a	self.stderr = io.TextIOWrapper(self.stderr)
694	n/a
695	n/a
696	n/a	def _translate_newlines(self, data, encoding):
697	n/a	data = data.replace(b"\r\n", b"\n").replace(b"\r", b"\n")
698	n/a	return data.decode(encoding)
699	n/a
700	n/a
701	n/a	def __del__(self, _maxsize=sys.maxsize, _active=_active):
702	n/a	if not self._child_created:
703	n/a	# We didn't get to successfully create a child process.
704	n/a	return
705	n/a	# In case the child hasn't been waited on, check if it's done.
706	n/a	self._internal_poll(_deadstate=_maxsize)
707	n/a	if self.returncode is None and _active is not None:
708	n/a	# Child is still running, keep us alive until we can wait on it.
709	n/a	_active.append(self)
710	n/a
711	n/a
712	n/a	def communicate(self, input=None):
713	n/a	"""Interact with process: Send data to stdin. Read data from
714	n/a	stdout and stderr, until end-of-file is reached. Wait for
715	n/a	process to terminate. The optional input argument should be a
716	n/a	string to be sent to the child process, or None, if no data
717	n/a	should be sent to the child.
718	n/a
719	n/a	communicate() returns a tuple (stdout, stderr)."""
720	n/a
721	n/a	# Optimization: If we are only using one pipe, or no pipe at
722	n/a	# all, using select() or threads is unnecessary.
723	n/a	if [self.stdin, self.stdout, self.stderr].count(None) >= 2:
724	n/a	stdout = None
725	n/a	stderr = None
726	n/a	if self.stdin:
727	n/a	if input:
728	n/a	self.stdin.write(input)
729	n/a	self.stdin.close()
730	n/a	elif self.stdout:
731	n/a	stdout = self.stdout.read()
732	n/a	self.stdout.close()
733	n/a	elif self.stderr:
734	n/a	stderr = self.stderr.read()
735	n/a	self.stderr.close()
736	n/a	self.wait()
737	n/a	return (stdout, stderr)
738	n/a
739	n/a	return self._communicate(input)
740	n/a
741	n/a
742	n/a	def poll(self):
743	n/a	return self._internal_poll()
744	n/a
745	n/a
746	n/a	if mswindows:
747	n/a	#
748	n/a	# Windows methods
749	n/a	#
750	n/a	def _get_handles(self, stdin, stdout, stderr):
751	n/a	"""Construct and return tuple with IO objects:
752	n/a	p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
753	n/a	"""
754	n/a	if stdin is None and stdout is None and stderr is None:
755	n/a	return (-1, -1, -1, -1, -1, -1)
756	n/a
757	n/a	p2cread, p2cwrite = -1, -1
758	n/a	c2pread, c2pwrite = -1, -1
759	n/a	errread, errwrite = -1, -1
760	n/a
761	n/a	if stdin is None:
762	n/a	p2cread = _subprocess.GetStdHandle(_subprocess.STD_INPUT_HANDLE)
763	n/a	if p2cread is None:
764	n/a	p2cread, _ = _subprocess.CreatePipe(None, 0)
765	n/a	elif stdin == PIPE:
766	n/a	p2cread, p2cwrite = _subprocess.CreatePipe(None, 0)
767	n/a	elif isinstance(stdin, int):
768	n/a	p2cread = msvcrt.get_osfhandle(stdin)
769	n/a	else:
770	n/a	# Assuming file-like object
771	n/a	p2cread = msvcrt.get_osfhandle(stdin.fileno())
772	n/a	p2cread = self._make_inheritable(p2cread)
773	n/a
774	n/a	if stdout is None:
775	n/a	c2pwrite = _subprocess.GetStdHandle(_subprocess.STD_OUTPUT_HANDLE)
776	n/a	if c2pwrite is None:
777	n/a	_, c2pwrite = _subprocess.CreatePipe(None, 0)
778	n/a	elif stdout == PIPE:
779	n/a	c2pread, c2pwrite = _subprocess.CreatePipe(None, 0)
780	n/a	elif isinstance(stdout, int):
781	n/a	c2pwrite = msvcrt.get_osfhandle(stdout)
782	n/a	else:
783	n/a	# Assuming file-like object
784	n/a	c2pwrite = msvcrt.get_osfhandle(stdout.fileno())
785	n/a	c2pwrite = self._make_inheritable(c2pwrite)
786	n/a
787	n/a	if stderr is None:
788	n/a	errwrite = _subprocess.GetStdHandle(_subprocess.STD_ERROR_HANDLE)
789	n/a	if errwrite is None:
790	n/a	_, errwrite = _subprocess.CreatePipe(None, 0)
791	n/a	elif stderr == PIPE:
792	n/a	errread, errwrite = _subprocess.CreatePipe(None, 0)
793	n/a	elif stderr == STDOUT:
794	n/a	errwrite = c2pwrite
795	n/a	elif isinstance(stderr, int):
796	n/a	errwrite = msvcrt.get_osfhandle(stderr)
797	n/a	else:
798	n/a	# Assuming file-like object
799	n/a	errwrite = msvcrt.get_osfhandle(stderr.fileno())
800	n/a	errwrite = self._make_inheritable(errwrite)
801	n/a
802	n/a	return (p2cread, p2cwrite,
803	n/a	c2pread, c2pwrite,
804	n/a	errread, errwrite)
805	n/a
806	n/a
807	n/a	def _make_inheritable(self, handle):
808	n/a	"""Return a duplicate of handle, which is inheritable"""
809	n/a	return _subprocess.DuplicateHandle(_subprocess.GetCurrentProcess(),
810	n/a	handle, _subprocess.GetCurrentProcess(), 0, 1,
811	n/a	_subprocess.DUPLICATE_SAME_ACCESS)
812	n/a
813	n/a
814	n/a	def _find_w9xpopen(self):
815	n/a	"""Find and return absolut path to w9xpopen.exe"""
816	n/a	w9xpopen = os.path.join(
817	n/a	os.path.dirname(_subprocess.GetModuleFileName(0)),
818	n/a	"w9xpopen.exe")
819	n/a	if not os.path.exists(w9xpopen):
820	n/a	# Eeek - file-not-found - possibly an embedding
821	n/a	# situation - see if we can locate it in sys.exec_prefix
822	n/a	w9xpopen = os.path.join(os.path.dirname(sys.exec_prefix),
823	n/a	"w9xpopen.exe")
824	n/a	if not os.path.exists(w9xpopen):
825	n/a	raise RuntimeError("Cannot locate w9xpopen.exe, which is "
826	n/a	"needed for Popen to work with your "
827	n/a	"shell or platform.")
828	n/a	return w9xpopen
829	n/a
830	n/a
831	n/a	def _execute_child(self, args, executable, preexec_fn, close_fds,
832	n/a	cwd, env, universal_newlines,
833	n/a	startupinfo, creationflags, shell,
834	n/a	p2cread, p2cwrite,
835	n/a	c2pread, c2pwrite,
836	n/a	errread, errwrite,
837	n/a	unused_restore_signals, unused_start_new_session):
838	n/a	"""Execute program (MS Windows version)"""
839	n/a
840	n/a	if not isinstance(args, str):
841	n/a	args = list2cmdline(args)
842	n/a
843	n/a	# Process startup details
844	n/a	if startupinfo is None:
845	n/a	startupinfo = STARTUPINFO()
846	n/a	if -1 not in (p2cread, c2pwrite, errwrite):
847	n/a	startupinfo.dwFlags \|= _subprocess.STARTF_USESTDHANDLES
848	n/a	startupinfo.hStdInput = p2cread
849	n/a	startupinfo.hStdOutput = c2pwrite
850	n/a	startupinfo.hStdError = errwrite
851	n/a
852	n/a	if shell:
853	n/a	startupinfo.dwFlags \|= _subprocess.STARTF_USESHOWWINDOW
854	n/a	startupinfo.wShowWindow = _subprocess.SW_HIDE
855	n/a	comspec = os.environ.get("COMSPEC", "cmd.exe")
856	n/a	args = comspec + " /c " + args
857	n/a	if (_subprocess.GetVersion() >= 0x80000000 or
858	n/a	os.path.basename(comspec).lower() == "command.com"):
859	n/a	# Win9x, or using command.com on NT. We need to
860	n/a	# use the w9xpopen intermediate program. For more
861	n/a	# information, see KB Q150956
862	n/a	# (http://web.archive.org/web/20011105084002/http://support.microsoft.com/support/kb/articles/Q150/9/56.asp)
863	n/a	w9xpopen = self._find_w9xpopen()
864	n/a	args = '"%s" %s' % (w9xpopen, args)
865	n/a	# Not passing CREATE_NEW_CONSOLE has been known to
866	n/a	# cause random failures on win9x. Specifically a
867	n/a	# dialog: "Your program accessed mem currently in
868	n/a	# use at xxx" and a hopeful warning about the
869	n/a	# stability of your system. Cost is Ctrl+C won't
870	n/a	# kill children.
871	n/a	creationflags \|= _subprocess.CREATE_NEW_CONSOLE
872	n/a
873	n/a	# Start the process
874	n/a	try:
875	n/a	hp, ht, pid, tid = _subprocess.CreateProcess(executable, args,
876	n/a	# no special security
877	n/a	None, None,
878	n/a	int(not close_fds),
879	n/a	creationflags,
880	n/a	env,
881	n/a	cwd,
882	n/a	startupinfo)
883	n/a	except pywintypes.error as e:
884	n/a	# Translate pywintypes.error to WindowsError, which is
885	n/a	# a subclass of OSError. FIXME: We should really
886	n/a	# translate errno using _sys_errlist (or simliar), but
887	n/a	# how can this be done from Python?
888	n/a	raise WindowsError(*e.args)
889	n/a
890	n/a	# Retain the process handle, but close the thread handle
891	n/a	self._child_created = True
892	n/a	self._handle = hp
893	n/a	self.pid = pid
894	n/a	ht.Close()
895	n/a
896	n/a	# Child is launched. Close the parent's copy of those pipe
897	n/a	# handles that only the child should have open. You need
898	n/a	# to make sure that no handles to the write end of the
899	n/a	# output pipe are maintained in this process or else the
900	n/a	# pipe will not close when the child process exits and the
901	n/a	# ReadFile will hang.
902	n/a	if p2cread != -1:
903	n/a	p2cread.Close()
904	n/a	if c2pwrite != -1:
905	n/a	c2pwrite.Close()
906	n/a	if errwrite != -1:
907	n/a	errwrite.Close()
908	n/a
909	n/a
910	n/a	def _internal_poll(self, _deadstate=None,
911	n/a	_WaitForSingleObject=_subprocess.WaitForSingleObject,
912	n/a	_WAIT_OBJECT_0=_subprocess.WAIT_OBJECT_0,
913	n/a	_GetExitCodeProcess=_subprocess.GetExitCodeProcess):
914	n/a	"""Check if child process has terminated. Returns returncode
915	n/a	attribute.
916	n/a
917	n/a	This method is called by __del__, so it can only refer to objects
918	n/a	in its local scope.
919	n/a
920	n/a	"""
921	n/a	if self.returncode is None:
922	n/a	if _WaitForSingleObject(self._handle, 0) == _WAIT_OBJECT_0:
923	n/a	self.returncode = _GetExitCodeProcess(self._handle)
924	n/a	return self.returncode
925	n/a
926	n/a
927	n/a	def wait(self):
928	n/a	"""Wait for child process to terminate. Returns returncode
929	n/a	attribute."""
930	n/a	if self.returncode is None:
931	n/a	_subprocess.WaitForSingleObject(self._handle,
932	n/a	_subprocess.INFINITE)
933	n/a	self.returncode = _subprocess.GetExitCodeProcess(self._handle)
934	n/a	return self.returncode
935	n/a
936	n/a
937	n/a	def _readerthread(self, fh, buffer):
938	n/a	buffer.append(fh.read())
939	n/a
940	n/a
941	n/a	def _communicate(self, input):
942	n/a	stdout = None # Return
943	n/a	stderr = None # Return
944	n/a
945	n/a	if self.stdout:
946	n/a	stdout = []
947	n/a	stdout_thread = threading.Thread(target=self._readerthread,
948	n/a	args=(self.stdout, stdout))
949	n/a	stdout_thread.daemon = True
950	n/a	stdout_thread.start()
951	n/a	if self.stderr:
952	n/a	stderr = []
953	n/a	stderr_thread = threading.Thread(target=self._readerthread,
954	n/a	args=(self.stderr, stderr))
955	n/a	stderr_thread.daemon = True
956	n/a	stderr_thread.start()
957	n/a
958	n/a	if self.stdin:
959	n/a	if input is not None:
960	n/a	self.stdin.write(input)
961	n/a	self.stdin.close()
962	n/a
963	n/a	if self.stdout:
964	n/a	stdout_thread.join()
965	n/a	if self.stderr:
966	n/a	stderr_thread.join()
967	n/a
968	n/a	# All data exchanged. Translate lists into strings.
969	n/a	if stdout is not None:
970	n/a	stdout = stdout[0]
971	n/a	if stderr is not None:
972	n/a	stderr = stderr[0]
973	n/a
974	n/a	self.wait()
975	n/a	return (stdout, stderr)
976	n/a
977	n/a	def send_signal(self, sig):
978	n/a	"""Send a signal to the process
979	n/a	"""
980	n/a	if sig == signal.SIGTERM:
981	n/a	self.terminate()
982	n/a	elif sig == signal.CTRL_C_EVENT:
983	n/a	os.kill(self.pid, signal.CTRL_C_EVENT)
984	n/a	elif sig == signal.CTRL_BREAK_EVENT:
985	n/a	os.kill(self.pid, signal.CTRL_BREAK_EVENT)
986	n/a	else:
987	n/a	raise ValueError("Only SIGTERM is supported on Windows")
988	n/a
989	n/a	def terminate(self):
990	n/a	"""Terminates the process
991	n/a	"""
992	n/a	_subprocess.TerminateProcess(self._handle, 1)
993	n/a
994	n/a	kill = terminate
995	n/a
996	n/a	else:
997	n/a	#
998	n/a	# POSIX methods
999	n/a	#
1000	n/a	def _get_handles(self, stdin, stdout, stderr):
1001	n/a	"""Construct and return tuple with IO objects:
1002	n/a	p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite
1003	n/a	"""
1004	n/a	p2cread, p2cwrite = -1, -1
1005	n/a	c2pread, c2pwrite = -1, -1
1006	n/a	errread, errwrite = -1, -1
1007	n/a
1008	n/a	if stdin is None:
1009	n/a	pass
1010	n/a	elif stdin == PIPE:
1011	n/a	p2cread, p2cwrite = os.pipe()
1012	n/a	elif isinstance(stdin, int):
1013	n/a	p2cread = stdin
1014	n/a	else:
1015	n/a	# Assuming file-like object
1016	n/a	p2cread = stdin.fileno()
1017	n/a
1018	n/a	if stdout is None:
1019	n/a	pass
1020	n/a	elif stdout == PIPE:
1021	n/a	c2pread, c2pwrite = os.pipe()
1022	n/a	elif isinstance(stdout, int):
1023	n/a	c2pwrite = stdout
1024	n/a	else:
1025	n/a	# Assuming file-like object
1026	n/a	c2pwrite = stdout.fileno()
1027	n/a
1028	n/a	if stderr is None:
1029	n/a	pass
1030	n/a	elif stderr == PIPE:
1031	n/a	errread, errwrite = os.pipe()
1032	n/a	elif stderr == STDOUT:
1033	n/a	errwrite = c2pwrite
1034	n/a	elif isinstance(stderr, int):
1035	n/a	errwrite = stderr
1036	n/a	else:
1037	n/a	# Assuming file-like object
1038	n/a	errwrite = stderr.fileno()
1039	n/a
1040	n/a	return (p2cread, p2cwrite,
1041	n/a	c2pread, c2pwrite,
1042	n/a	errread, errwrite)
1043	n/a
1044	n/a
1045	n/a	def _set_cloexec_flag(self, fd):
1046	n/a	try:
1047	n/a	cloexec_flag = fcntl.FD_CLOEXEC
1048	n/a	except AttributeError:
1049	n/a	cloexec_flag = 1
1050	n/a
1051	n/a	old = fcntl.fcntl(fd, fcntl.F_GETFD)
1052	n/a	fcntl.fcntl(fd, fcntl.F_SETFD, old \| cloexec_flag)
1053	n/a
1054	n/a
1055	n/a	def _close_fds(self, but):
1056	n/a	os.closerange(3, but)
1057	n/a	os.closerange(but + 1, MAXFD)
1058	n/a
1059	n/a
1060	n/a	def _execute_child(self, args, executable, preexec_fn, close_fds,
1061	n/a	cwd, env, universal_newlines,
1062	n/a	startupinfo, creationflags, shell,
1063	n/a	p2cread, p2cwrite,
1064	n/a	c2pread, c2pwrite,
1065	n/a	errread, errwrite,
1066	n/a	restore_signals, start_new_session):
1067	n/a	"""Execute program (POSIX version)"""
1068	n/a
1069	n/a	if isinstance(args, str):
1070	n/a	args = [args]
1071	n/a	else:
1072	n/a	args = list(args)
1073	n/a
1074	n/a	if shell:
1075	n/a	args = ["/bin/sh", "-c"] + args
1076	n/a	if executable:
1077	n/a	args[0] = executable
1078	n/a
1079	n/a	if executable is None:
1080	n/a	executable = args[0]
1081	n/a
1082	n/a	# For transferring possible exec failure from child to parent.
1083	n/a	# Data format: "exception name:hex errno:description"
1084	n/a	# Pickle is not used; it is complex and involves memory allocation.
1085	n/a	errpipe_read, errpipe_write = os.pipe()
1086	n/a	try:
1087	n/a	try:
1088	n/a	self._set_cloexec_flag(errpipe_write)
1089	n/a
1090	n/a	if _posixsubprocess:
1091	n/a	# We must avoid complex work that could involve
1092	n/a	# malloc or free in the child process to avoid
1093	n/a	# potential deadlocks, thus we do all this here.
1094	n/a	# and pass it to fork_exec()
1095	n/a
1096	n/a	if env:
1097	n/a	env_list = [os.fsencode(k) + b'=' + os.fsencode(v)
1098	n/a	for k, v in env.items()]
1099	n/a	else:
1100	n/a	env_list = None # Use execv instead of execve.
1101	n/a	executable = os.fsencode(executable)
1102	n/a	if os.path.dirname(executable):
1103	n/a	executable_list = (executable,)
1104	n/a	else:
1105	n/a	# This matches the behavior of os._execvpe().
1106	n/a	executable_list = tuple(
1107	n/a	os.path.join(os.fsencode(dir), executable)
1108	n/a	for dir in os.get_exec_path(env))
1109	n/a	self.pid = _posixsubprocess.fork_exec(
1110	n/a	args, executable_list,
1111	n/a	close_fds, cwd, env_list,
1112	n/a	p2cread, p2cwrite, c2pread, c2pwrite,
1113	n/a	errread, errwrite,
1114	n/a	errpipe_read, errpipe_write,
1115	n/a	restore_signals, start_new_session, preexec_fn)
1116	n/a	else:
1117	n/a	# Pure Python implementation: It is not thread safe.
1118	n/a	# This implementation may deadlock in the child if your
1119	n/a	# parent process has any other threads running.
1120	n/a
1121	n/a	gc_was_enabled = gc.isenabled()
1122	n/a	# Disable gc to avoid bug where gc -> file_dealloc ->
1123	n/a	# write to stderr -> hang. See issue1336
1124	n/a	gc.disable()
1125	n/a	try:
1126	n/a	self.pid = os.fork()
1127	n/a	except:
1128	n/a	if gc_was_enabled:
1129	n/a	gc.enable()
1130	n/a	raise
1131	n/a	self._child_created = True
1132	n/a	if self.pid == 0:
1133	n/a	# Child
1134	n/a	try:
1135	n/a	# Close parent's pipe ends
1136	n/a	if p2cwrite != -1:
1137	n/a	os.close(p2cwrite)
1138	n/a	if c2pread != -1:
1139	n/a	os.close(c2pread)
1140	n/a	if errread != -1:
1141	n/a	os.close(errread)
1142	n/a	os.close(errpipe_read)
1143	n/a
1144	n/a	# Dup fds for child
1145	n/a	if p2cread != -1:
1146	n/a	os.dup2(p2cread, 0)
1147	n/a	if c2pwrite != -1:
1148	n/a	os.dup2(c2pwrite, 1)
1149	n/a	if errwrite != -1:
1150	n/a	os.dup2(errwrite, 2)
1151	n/a
1152	n/a	# Close pipe fds. Make sure we don't close the
1153	n/a	# same fd more than once, or standard fds.
1154	n/a	if p2cread != -1 and p2cread not in (0,):
1155	n/a	os.close(p2cread)
1156	n/a	if (c2pwrite != -1 and
1157	n/a	c2pwrite not in (p2cread, 1)):
1158	n/a	os.close(c2pwrite)
1159	n/a	if (errwrite != -1 and
1160	n/a	errwrite not in (p2cread, c2pwrite, 2)):
1161	n/a	os.close(errwrite)
1162	n/a
1163	n/a	# Close all other fds, if asked for
1164	n/a	if close_fds:
1165	n/a	self._close_fds(but=errpipe_write)
1166	n/a
1167	n/a	if cwd is not None:
1168	n/a	os.chdir(cwd)
1169	n/a
1170	n/a	# This is a copy of Python/pythonrun.c
1171	n/a	# _Py_RestoreSignals(). If that were exposed
1172	n/a	# as a sys._py_restoresignals func it would be
1173	n/a	# better.. but this pure python implementation
1174	n/a	# isn't likely to be used much anymore.
1175	n/a	if restore_signals:
1176	n/a	signals = ('SIGPIPE', 'SIGXFZ', 'SIGXFSZ')
1177	n/a	for sig in signals:
1178	n/a	if hasattr(signal, sig):
1179	n/a	signal.signal(getattr(signal, sig),
1180	n/a	signal.SIG_DFL)
1181	n/a
1182	n/a	if start_new_session and hasattr(os, 'setsid'):
1183	n/a	os.setsid()
1184	n/a
1185	n/a	if preexec_fn:
1186	n/a	preexec_fn()
1187	n/a
1188	n/a	if env is None:
1189	n/a	os.execvp(executable, args)
1190	n/a	else:
1191	n/a	os.execvpe(executable, args, env)
1192	n/a
1193	n/a	except:
1194	n/a	try:
1195	n/a	exc_type, exc_value = sys.exc_info()[:2]
1196	n/a	if isinstance(exc_value, OSError):
1197	n/a	errno = exc_value.errno
1198	n/a	else:
1199	n/a	errno = 0
1200	n/a	message = '%s:%x:%s' % (exc_type.__name__,
1201	n/a	errno, exc_value)
1202	n/a	message = message.encode(errors="surrogatepass")
1203	n/a	os.write(errpipe_write, message)
1204	n/a	except Exception:
1205	n/a	# We MUST not allow anything odd happening
1206	n/a	# above to prevent us from exiting below.
1207	n/a	pass
1208	n/a
1209	n/a	# This exitcode won't be reported to applications
1210	n/a	# so it really doesn't matter what we return.
1211	n/a	os._exit(255)
1212	n/a
1213	n/a	# Parent
1214	n/a	if gc_was_enabled:
1215	n/a	gc.enable()
1216	n/a	finally:
1217	n/a	# be sure the FD is closed no matter what
1218	n/a	os.close(errpipe_write)
1219	n/a
1220	n/a	if p2cread != -1 and p2cwrite != -1:
1221	n/a	os.close(p2cread)
1222	n/a	if c2pwrite != -1 and c2pread != -1:
1223	n/a	os.close(c2pwrite)
1224	n/a	if errwrite != -1 and errread != -1:
1225	n/a	os.close(errwrite)
1226	n/a
1227	n/a	# Wait for exec to fail or succeed; possibly raising an
1228	n/a	# exception (limited in size)
1229	n/a	data = bytearray()
1230	n/a	while True:
1231	n/a	part = _eintr_retry_call(os.read, errpipe_read, 50000)
1232	n/a	data += part
1233	n/a	if not part or len(data) > 50000:
1234	n/a	break
1235	n/a	finally:
1236	n/a	# be sure the FD is closed no matter what
1237	n/a	os.close(errpipe_read)
1238	n/a
1239	n/a	if data:
1240	n/a	_eintr_retry_call(os.waitpid, self.pid, 0)
1241	n/a	try:
1242	n/a	exception_name, hex_errno, err_msg = data.split(b':', 2)
1243	n/a	except ValueError:
1244	n/a	print('Bad exception data:', repr(data))
1245	n/a	exception_name = b'RuntimeError'
1246	n/a	hex_errno = b'0'
1247	n/a	err_msg = b'Unknown'
1248	n/a	child_exception_type = getattr(
1249	n/a	builtins, exception_name.decode('ascii'),
1250	n/a	RuntimeError)
1251	n/a	for fd in (p2cwrite, c2pread, errread):
1252	n/a	if fd != -1:
1253	n/a	os.close(fd)
1254	n/a	err_msg = err_msg.decode(errors="surrogatepass")
1255	n/a	if issubclass(child_exception_type, OSError) and hex_errno:
1256	n/a	errno = int(hex_errno, 16)
1257	n/a	if errno != 0:
1258	n/a	err_msg = os.strerror(errno)
1259	n/a	raise child_exception_type(errno, err_msg)
1260	n/a	raise child_exception_type(err_msg)
1261	n/a
1262	n/a
1263	n/a	def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED,
1264	n/a	_WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED,
1265	n/a	_WEXITSTATUS=os.WEXITSTATUS):
1266	n/a	# This method is called (indirectly) by __del__, so it cannot
1267	n/a	# refer to anything outside of its local scope."""
1268	n/a	if _WIFSIGNALED(sts):
1269	n/a	self.returncode = -_WTERMSIG(sts)
1270	n/a	elif _WIFEXITED(sts):
1271	n/a	self.returncode = _WEXITSTATUS(sts)
1272	n/a	else:
1273	n/a	# Should never happen
1274	n/a	raise RuntimeError("Unknown child exit status!")
1275	n/a
1276	n/a
1277	n/a	def _internal_poll(self, _deadstate=None, _waitpid=os.waitpid,
1278	n/a	_WNOHANG=os.WNOHANG, _os_error=os.error):
1279	n/a	"""Check if child process has terminated. Returns returncode
1280	n/a	attribute.
1281	n/a
1282	n/a	This method is called by __del__, so it cannot reference anything
1283	n/a	outside of the local scope (nor can any methods it calls).
1284	n/a
1285	n/a	"""
1286	n/a	if self.returncode is None:
1287	n/a	try:
1288	n/a	pid, sts = _waitpid(self.pid, _WNOHANG)
1289	n/a	if pid == self.pid:
1290	n/a	self._handle_exitstatus(sts)
1291	n/a	except _os_error:
1292	n/a	if _deadstate is not None:
1293	n/a	self.returncode = _deadstate
1294	n/a	return self.returncode
1295	n/a
1296	n/a
1297	n/a	def wait(self):
1298	n/a	"""Wait for child process to terminate. Returns returncode
1299	n/a	attribute."""
1300	n/a	if self.returncode is None:
1301	n/a	pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
1302	n/a	self._handle_exitstatus(sts)
1303	n/a	return self.returncode
1304	n/a
1305	n/a
1306	n/a	def _communicate(self, input):
1307	n/a	if self.stdin:
1308	n/a	# Flush stdio buffer. This might block, if the user has
1309	n/a	# been writing to .stdin in an uncontrolled fashion.
1310	n/a	self.stdin.flush()
1311	n/a	if not input:
1312	n/a	self.stdin.close()
1313	n/a
1314	n/a	if _has_poll:
1315	n/a	stdout, stderr = self._communicate_with_poll(input)
1316	n/a	else:
1317	n/a	stdout, stderr = self._communicate_with_select(input)
1318	n/a
1319	n/a	# All data exchanged. Translate lists into strings.
1320	n/a	if stdout is not None:
1321	n/a	stdout = b''.join(stdout)
1322	n/a	if stderr is not None:
1323	n/a	stderr = b''.join(stderr)
1324	n/a
1325	n/a	# Translate newlines, if requested.
1326	n/a	# This also turns bytes into strings.
1327	n/a	if self.universal_newlines:
1328	n/a	if stdout is not None:
1329	n/a	stdout = self._translate_newlines(stdout,
1330	n/a	self.stdout.encoding)
1331	n/a	if stderr is not None:
1332	n/a	stderr = self._translate_newlines(stderr,
1333	n/a	self.stderr.encoding)
1334	n/a
1335	n/a	self.wait()
1336	n/a	return (stdout, stderr)
1337	n/a
1338	n/a
1339	n/a	def _communicate_with_poll(self, input):
1340	n/a	stdout = None # Return
1341	n/a	stderr = None # Return
1342	n/a	fd2file = {}
1343	n/a	fd2output = {}
1344	n/a
1345	n/a	poller = select.poll()
1346	n/a	def register_and_append(file_obj, eventmask):
1347	n/a	poller.register(file_obj.fileno(), eventmask)
1348	n/a	fd2file[file_obj.fileno()] = file_obj
1349	n/a
1350	n/a	def close_unregister_and_remove(fd):
1351	n/a	poller.unregister(fd)
1352	n/a	fd2file[fd].close()
1353	n/a	fd2file.pop(fd)
1354	n/a
1355	n/a	if self.stdin and input:
1356	n/a	register_and_append(self.stdin, select.POLLOUT)
1357	n/a
1358	n/a	select_POLLIN_POLLPRI = select.POLLIN \| select.POLLPRI
1359	n/a	if self.stdout:
1360	n/a	register_and_append(self.stdout, select_POLLIN_POLLPRI)
1361	n/a	fd2output[self.stdout.fileno()] = stdout = []
1362	n/a	if self.stderr:
1363	n/a	register_and_append(self.stderr, select_POLLIN_POLLPRI)
1364	n/a	fd2output[self.stderr.fileno()] = stderr = []
1365	n/a
1366	n/a	input_offset = 0
1367	n/a	while fd2file:
1368	n/a	try:
1369	n/a	ready = poller.poll()
1370	n/a	except select.error as e:
1371	n/a	if e.args[0] == errno.EINTR:
1372	n/a	continue
1373	n/a	raise
1374	n/a
1375	n/a	# XXX Rewrite these to use non-blocking I/O on the
1376	n/a	# file objects; they are no longer using C stdio!
1377	n/a
1378	n/a	for fd, mode in ready:
1379	n/a	if mode & select.POLLOUT:
1380	n/a	chunk = input[input_offset : input_offset + _PIPE_BUF]
1381	n/a	input_offset += os.write(fd, chunk)
1382	n/a	if input_offset >= len(input):
1383	n/a	close_unregister_and_remove(fd)
1384	n/a	elif mode & select_POLLIN_POLLPRI:
1385	n/a	data = os.read(fd, 4096)
1386	n/a	if not data:
1387	n/a	close_unregister_and_remove(fd)
1388	n/a	fd2output[fd].append(data)
1389	n/a	else:
1390	n/a	# Ignore hang up or errors.
1391	n/a	close_unregister_and_remove(fd)
1392	n/a
1393	n/a	return (stdout, stderr)
1394	n/a
1395	n/a
1396	n/a	def _communicate_with_select(self, input):
1397	n/a	read_set = []
1398	n/a	write_set = []
1399	n/a	stdout = None # Return
1400	n/a	stderr = None # Return
1401	n/a
1402	n/a	if self.stdin and input:
1403	n/a	write_set.append(self.stdin)
1404	n/a	if self.stdout:
1405	n/a	read_set.append(self.stdout)
1406	n/a	stdout = []
1407	n/a	if self.stderr:
1408	n/a	read_set.append(self.stderr)
1409	n/a	stderr = []
1410	n/a
1411	n/a	input_offset = 0
1412	n/a	while read_set or write_set:
1413	n/a	try:
1414	n/a	rlist, wlist, xlist = select.select(read_set, write_set, [])
1415	n/a	except select.error as e:
1416	n/a	if e.args[0] == errno.EINTR:
1417	n/a	continue
1418	n/a	raise
1419	n/a
1420	n/a	# XXX Rewrite these to use non-blocking I/O on the
1421	n/a	# file objects; they are no longer using C stdio!
1422	n/a
1423	n/a	if self.stdin in wlist:
1424	n/a	chunk = input[input_offset : input_offset + _PIPE_BUF]
1425	n/a	bytes_written = os.write(self.stdin.fileno(), chunk)
1426	n/a	input_offset += bytes_written
1427	n/a	if input_offset >= len(input):
1428	n/a	self.stdin.close()
1429	n/a	write_set.remove(self.stdin)
1430	n/a
1431	n/a	if self.stdout in rlist:
1432	n/a	data = os.read(self.stdout.fileno(), 1024)
1433	n/a	if not data:
1434	n/a	self.stdout.close()
1435	n/a	read_set.remove(self.stdout)
1436	n/a	stdout.append(data)
1437	n/a
1438	n/a	if self.stderr in rlist:
1439	n/a	data = os.read(self.stderr.fileno(), 1024)
1440	n/a	if not data:
1441	n/a	self.stderr.close()
1442	n/a	read_set.remove(self.stderr)
1443	n/a	stderr.append(data)
1444	n/a
1445	n/a	return (stdout, stderr)
1446	n/a
1447	n/a
1448	n/a	def send_signal(self, sig):
1449	n/a	"""Send a signal to the process
1450	n/a	"""
1451	n/a	os.kill(self.pid, sig)
1452	n/a
1453	n/a	def terminate(self):
1454	n/a	"""Terminate the process with SIGTERM
1455	n/a	"""
1456	n/a	self.send_signal(signal.SIGTERM)
1457	n/a
1458	n/a	def kill(self):
1459	n/a	"""Kill the process with SIGKILL
1460	n/a	"""
1461	n/a	self.send_signal(signal.SIGKILL)
1462	n/a
1463	n/a
1464	n/a	def _demo_posix():
1465	n/a	#
1466	n/a	# Example 1: Simple redirection: Get process list
1467	n/a	#
1468	n/a	plist = Popen(["ps"], stdout=PIPE).communicate()[0]
1469	n/a	print("Process list:")
1470	n/a	print(plist)
1471	n/a
1472	n/a	#
1473	n/a	# Example 2: Change uid before executing child
1474	n/a	#
1475	n/a	if os.getuid() == 0:
1476	n/a	p = Popen(["id"], preexec_fn=lambda: os.setuid(100))
1477	n/a	p.wait()
1478	n/a
1479	n/a	#
1480	n/a	# Example 3: Connecting several subprocesses
1481	n/a	#
1482	n/a	print("Looking for 'hda'...")
1483	n/a	p1 = Popen(["dmesg"], stdout=PIPE)
1484	n/a	p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
1485	n/a	print(repr(p2.communicate()[0]))
1486	n/a
1487	n/a	#
1488	n/a	# Example 4: Catch execution error
1489	n/a	#
1490	n/a	print()
1491	n/a	print("Trying a weird file...")
1492	n/a	try:
1493	n/a	print(Popen(["/this/path/does/not/exist"]).communicate())
1494	n/a	except OSError as e:
1495	n/a	if e.errno == errno.ENOENT:
1496	n/a	print("The file didn't exist. I thought so...")
1497	n/a	print("Child traceback:")
1498	n/a	print(e.child_traceback)
1499	n/a	else:
1500	n/a	print("Error", e.errno)
1501	n/a	else:
1502	n/a	print("Gosh. No error.", file=sys.stderr)
1503	n/a
1504	n/a
1505	n/a	def _demo_windows():
1506	n/a	#
1507	n/a	# Example 1: Connecting several subprocesses
1508	n/a	#
1509	n/a	print("Looking for 'PROMPT' in set output...")
1510	n/a	p1 = Popen("set", stdout=PIPE, shell=True)
1511	n/a	p2 = Popen('find "PROMPT"', stdin=p1.stdout, stdout=PIPE)
1512	n/a	print(repr(p2.communicate()[0]))
1513	n/a
1514	n/a	#
1515	n/a	# Example 2: Simple execution of program
1516	n/a	#
1517	n/a	print("Executing calc...")
1518	n/a	p = Popen("calc")
1519	n/a	p.wait()
1520	n/a
1521	n/a
1522	n/a	if __name__ == "__main__":
1523	n/a	if mswindows:
1524	n/a	_demo_windows()
1525	n/a	else:
1526	n/a	_demo_posix()