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Comment by dpritchett | Hacker News Reader

I shamelessly reach for the backtick shell notation in any exploratory Ruby code that needs it. I try to replace it with something written in Ruby if the codebase grows beyond my laptop, but backticks never get old.

    => 1.upto(100) { |n| puts `curl -s fizzy.heroku.com/#{n}` }

    1
    2
    Fizz
    4
    Buzz
    ...

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Ha! That backtick is the only reason most of my "scripts" are being written in Ruby instead of Python. :)

Seems pretty easy in python:

  from subprocess import call
  call(["ls", "-l"])

  import os
  os.system("ls -l")

While there are several ways to skin that cat, the suggested way is to use subprocess.Popen .

Also, when using Popen, calling .wait() can cause problems if you are expecting large amounts of info back from stdin or stderr. Using .communicate() is generally better.

this. python has too many ways to skin the cat.

hehe, while I do agree in this particular situation, it's rather funny to see that in writing.

The difference between "pretty easy" and "easy" changes everything.

Compare

  from subprocess import call
  call(["ls", "-l"])

  `ls -l`

I really like the python sh library for stuff like this. Would you rather do what you wrote, or this?

    for listing in ls('-l'):
        '''etc'''

Here's the library in question - https://pypi.python.org/pypi/pbs - it makes me super happy to do shell work in python.

Wow, that's a neat library. You can just import any program and use it like a function (from sh import grep)! Thanks for the link. Also, sh documentation: http://amoffat.github.io/sh/

i use Sh to interface with my cmus player. from sh import cmus_remote! :)

Yeah, it's replaced just a ton of boilerplate `def run(*args):` functions wrapping Popen. I couldn't be happier.

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