Python as a scripting language. Alternative to bash script?

[Thomas Jollans]

On 06/28/2010 06:08 PM, Dave Pawson wrote:
> Thanks for the replies (and Benjamin).
> Not met with the subprocess idea.
> 
> On 28 June 2010 16:29, D'Arcy J.M. Cain <darcy at druid.net> wrote:
> 
>>> Main queries are:
>>> Ease of calling out to bash to use something like imageMagick or Java?
>>
>> You don't need to call bash to call an external program.  Check out the
>> subprocess module.
> 
> Will do.
> 
>   If you do need a shell to simplify calling a
>> program (environment and wild card expansione.g.) don't call bash.
> 
> I can get what I want from Python. No envars needed.
> 
> 
> 
>>> Ease of grabbing return parameters? E.g. convert can return both
>>> height and width of an image. Can this be returned to the Python program?
>>
>> Just to set the terminology straight, a parameter is what you call the
>> function with.  The return value is what it returns.  The program
>> output is what it emits (prints.)
> 
> My bad. I mean return values, though I do want
> program out from (for example) identify

If you're working with images, have a look at the PIL (Python Imaging
Library).

> 
> 
>>
>> Programs return an integer value.  This is also called the exit
>> status.
> 
> Sheer greed, for identify I may get either a return value or an exit
> status (bad input etc) :-)
> Looks like subprocess can hack it though.
> 
>>
>> What you want is the output of the program.  For this you need to
>> capture the output and parse it.
>>
>> Look at the subprocess module.
> 
> Will do.
> tks D'Arcy (and Benjamin)
> 
> 
> 
> 
>