当使用Python的子进程模块和communication()方法时，我如何检索退出代码?
相关代码:
import subprocess as sp
data = sp.Popen(openRTSP + opts.split(), stdout=sp.PIPE).communicate()[0]
我应该换一种方法吗?
当前回答
请看评论。
代码:
import subprocess
class MyLibrary(object):
def execute(self, cmd):
return subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, universal_newlines=True,)
def list(self):
command = ["ping", "google.com"]
sp = self.execute(command)
status = sp.wait() # will wait for sp to finish
out, err = sp.communicate()
print(out)
return status # 0 is success else error
test = MyLibrary()
print(test.list())
输出:
C:\Users\shita\Documents\Tech\Python>python t5.py
Pinging google.com [142.250.64.78] with 32 bytes of data:
Reply from 142.250.64.78: bytes=32 time=108ms TTL=116
Reply from 142.250.64.78: bytes=32 time=224ms TTL=116
Reply from 142.250.64.78: bytes=32 time=84ms TTL=116
Reply from 142.250.64.78: bytes=32 time=139ms TTL=116
Ping statistics for 142.250.64.78:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 84ms, Maximum = 224ms, Average = 138ms
0
其他回答
这对我很管用。它还打印子进程返回的输出
child = subprocess.Popen(serial_script_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
retValRunJobsSerialScript = 0
for line in child.stdout.readlines():
child.wait()
print line
retValRunJobsSerialScript= child.returncode
在调用process. communication()之后使用process.wait()。 例如:
import subprocess
process = subprocess.Popen(['ipconfig', '/all'], stderr=subprocess.PIPE, stdout=subprocess.PIPE)
stdout, stderr = process.communicate()
exit_code = process.wait()
print(stdout, stderr, exit_code)
首先，您应该确保进程已经完成运行，并且已经使用.wait方法读取了返回代码。这将返回代码。如果你以后想要访问它，它被存储为Popen对象中的.returncode。
.poll()将更新返回代码。
Try
child = sp.Popen(openRTSP + opts.split(), stdout=sp.PIPE)
returnCode = child.poll()
此外，在.poll()被调用之后，返回代码可以作为child.returncode在对象中使用。
请看评论。
代码:
import subprocess
class MyLibrary(object):
def execute(self, cmd):
return subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, universal_newlines=True,)
def list(self):
command = ["ping", "google.com"]
sp = self.execute(command)
status = sp.wait() # will wait for sp to finish
out, err = sp.communicate()
print(out)
return status # 0 is success else error
test = MyLibrary()
print(test.list())
输出:
C:\Users\shita\Documents\Tech\Python>python t5.py
Pinging google.com [142.250.64.78] with 32 bytes of data:
Reply from 142.250.64.78: bytes=32 time=108ms TTL=116
Reply from 142.250.64.78: bytes=32 time=224ms TTL=116
Reply from 142.250.64.78: bytes=32 time=84ms TTL=116
Reply from 142.250.64.78: bytes=32 time=139ms TTL=116
Ping statistics for 142.250.64.78:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 84ms, Maximum = 224ms, Average = 138ms
0
