ANN: Version 0.1.5 of sarge (a subprocess wrapper library) has been released.

[Vinay Sajip]

Version 0.1.5 of Sarge, a cross-platform library which wraps the subprocess

module in the standard library, has been released.

What changed?

-------------

- Fixed #37: Instead of an OSError with a "no such file or directory" message,

  a ValueError is raised with a more informative "Command not found" message.

- Fixed #38: Replaced ``async`` keyword argument with ``async_``, as ``async``

  has become a keyword in Python 3.7.

- Fixed #39: Updated tutorial example on progress monitoring.

What does Sarge do?

-------------------

Sarge tries to make interfacing with external programs from your

Python applications easier than just using subprocess alone.

Sarge offers the following features:

* A simple way to run command lines which allows a rich subset of Bash-

style shell command syntax, but parsed and run by sarge so that you

can run on Windows without cygwin (subject to having those commands

available):

>>> from sarge import capture_stdout

>>> p = capture_stdout('echo foo | cat; echo bar')

>>> for line in p.stdout: print(repr(line))

...

'foo\n'

'bar\n'

* The ability to format shell commands with placeholders, such that

variables are quoted to prevent shell injection attacks.

* The ability to capture output streams without requiring you to

program your own threads. You just use a Capture object and then you

can read from it as and when you want.

* The ability to look for patterns in captured output and to interact

accordingly with the child process.

Advantages over subprocess

---------------------------

Sarge offers the following benefits compared to using subprocess:

* The API is very simple.

* It's easier to use command pipelines - using subprocess out of the

box often leads to deadlocks because pipe buffers get filled up.

* It would be nice to use Bash-style pipe syntax on Windows, but

Windows shells don't support some of the syntax which is useful, like

&&, ||, |& and so on. Sarge gives you that functionality on Windows,

without cygwin.

* Sometimes, subprocess.Popen.communicate() is not flexible enough for

one's needs - for example, when one needs to process output a line at

a time without buffering the entire output in memory.

* It's desirable to avoid shell injection problems by having the

ability to quote command arguments safely.

* subprocess allows you to let stderr be the same as stdout, but not

the other way around - and sometimes, you need to do that.

Python version and platform compatibility

-----------------------------------------

Sarge is intended to be used on any Python version >= 2.6 and is

tested on Python versions 2.6, 2.7, 3.3, 3.4, 3.5, 3.6 and 3.7 on Linux,

Windows, and Mac OS X (not all versions are tested on all platforms,

but sarge is expected to work correctly on all these versions on all

these platforms).

Finding out more

----------------

You can read the documentation at

http://sarge.readthedocs.org/

There's a lot more information, with examples, than I can put into

this post.

You can install Sarge using "pip install sarge" to try it out. The

project is hosted on BitBucket at

https://bitbucket.org/vinay.sajip/sarge/

And you can leave feedback on the issue tracker there.

I hope you find Sarge useful!

Regards,

Vinay Sajip