How can I append each output of subprocess into a list?

I'm trying to take the output of p5, they are mac address, and I want to store them into a list.

I know that mac addresses are printed in byte type but I can't manage to get them in the type I want.

p3 = subprocess.Popen(["iw", "dev", displayInt, "station", "dump"], stdout=subprocess.PIPE)

p4 = subprocess.Popen(["grep", "Station"], stdin=p3.stdout,  stdout=subprocess.PIPE)

p5 = subprocess.Popen(["cut", "-f", "2", "-s", "-d", " "], stdin=p4.stdout, stdout=subprocess.PIPE)

for line in iter(p5.stdout.readline,''):
    maclist.append(line.rstrip('\n'))
print(maclist)

I would like to have an output like:

[a1:b2:c3:d4:e5:f6 , a1:b2:c3:d4:e5:f6]

And I'm getting the following error:

TypeError: a bytes-like object is required, not 'str'

Solution

It seems you are using Python 3. In Python 3, stdout is a stream of bytes. If you want to convert that into string, add the encoding='utf8' paramter to the Popen() call, for example:

p5 = subprocess.Popen(
    ["cut", "-f", "2", "-s", "-d", " "],
    encoding="utf8",
    stdin=p4.stdout,
    stdout=subprocess.PIPE)

You might have to include the encoding parameter for other calls. Also, instead of:

for line in iter(p5.stdout.readline,''):

You might want to try this, which is shorter and easier to understand:

for line in p5.stdout: