Question

I just learned subprocess.check_call() function today. I intend to use it to replace my os.system command.

Originally, I have my command as such:

os.system("mount -t cifs //source/share /mnt/share -o username=user")

The command above will prompt for password and it will mount the drive if the password is correct.

However, if I tried:

cmd_string="mount -t cifs //source/share /mnt/share -o username=user"

subprocess.check_call(cmd_string.split(" "), shell=True, stdin=sys.stdin)

It would not ask for password. Instead, it just print the partitions. It’s like invoke “mount” command without parameters.

Any idea how I can use check_call and still receive interactive input from user?

Answer 1

You are invoking mount without parameters. If you specify shell=True, subprocess expects the entire command including arguments is passed to the shell as one big string. If you specify shell=False (the default if not specified), the command and its arguments are passed as a list of strings, as you have done by using split. By mixing the two forms, you are effectively only passing the string mount as the command to be executed. Either remove shell=True or remove the .split(" "). The first choice is usually better unless there is some reason you need shell parsing to be involved, normally something to be avoided.