the below code shows attribute error when run the below code. import subprocess import sys import shlex
cmd = 'mtr -nrc30 -s1400 -z'
cmd = shlex.split(cmd)
abc = shlex.split(sys.argv[1])
subprocess.call([cmd,abc])
the error i get is below. What could the possible reason for this, when both the inputs to subprocess are converted to list
AttributeError: 'list' object has no attribute 'rfind'
For the sake of helping others with the same question: the issue here is this:
subprocess.call([cmd, abc])
where abc is a list of arguments you want to give the program specified in cmd, which were given to your program through sys.argv. What your current code ends up unpacking to, then, is the following:
# assume abc == ['arg1', 'arg2', ...]
subprocess.call([['mtr', '-nrc30', '-s1400', '-z'], ['arg1', 'arg2', ...]])
This isn't working, because it's a nested list. Subprocess only takes strings or a list of strings - so, to make it work, what you really want is
subprocess.call(['mtr', '-nrc30', '-s1400', '-z', 'arg1', 'arg2', ...])
This can be obtained by simply concatenating the two lists using +:
subprocess.call(cmd + abc)
shlex.split()returns a list. So your argument tosubprocess.call()is a list-of-lists, which is the wrong type.