在python subprocess.Popen（）中传递带两个引号的shell命令

Question

我试图在python代码中运行下一个命令：

iostat -d 7 7 -p sda | awk '!/^Device/' | awk '!/^Linux/'

到目前为止，我尝试的方式是：

command = ["iostat", "-d", "7", "7", "-p", "sda", "|", "awk", "'!/^Device/'", "|", "awk", "'!/^Linux/'"]
device = subprocess.Popen(command, stdout=subprocess.PIPE)
devicetr = device.stdout.read()

代码似乎无法按预期处理"'!/^Device/'"和"'!/^Linux/'"中的引号，如'!/^Device/'和'!/^Linux/'

当没有USB连接时，我得到的不是空白：

Linux 4.14.98-v7+   01/28/2020  _armv7l_    (4 CPU)

Device:            tps    kB_read/s    kB_wrtn/s    kB_read    kB_wrtn

Device:            tps    kB_read/s    kB_wrtn/s    kB_read    kB_wrtn

Device:            tps    kB_read/s    kB_wrtn/s    kB_read    kB_wrtn

已尝试添加'\'，并且： Passing double quote shell commands in python to subprocess.Popen()?

Answer 1

1. 您不需要添加额外的引号，因为subprocess会在需要时自动添加引号

command = ["iostat", "-d", "7", "7", "-p", "sda", "|", "awk", "!/^Device/", "|", "awk", "!/^Linux/"]
device = subprocess.Popen(command, stdout=subprocess.PIPE)
devicetr = device.stdout.read()  # also here was a typo red -> read

1. 正如@noufal-ibrahim pointer out |不以这种方式工作。您需要通过管道传输命令：

ps1 = subprocess.Popen(["iostat"], stdout=subprocess.PIPE)
ps2 = subprocess.Popen(["awk",  "!/^ *KB/"], stdin=ps1.stdout, stdout=subprocess.PIPE)  # filter out line with KB and extra space
print(ps2.stdout.read().decode())

^此代码适用于我的机器，您可以根据自己的使用情况进行调整

附录。您可以使用shlex库（来自标准python库），而不是手动创建命令列表：

>>> import shlex
>>> shlex.split("python foo.py 'multi word arg'")
['python', 'foo.py', 'multi word arg']