Get supported_archs from command line

[Ryan Schmidt]

> On Aug 3, 2016, at 10:48 AM, Joshua Root <jmr at macports.org> wrote:
> 
> On 2016-8-3 17:48 , Ryan Schmidt wrote:
>> I'd like to know a port's supported_archs from a command line script.
>> 
>> "port info" doesn't appear to have a flag to display it.
>> 
>> This Tcl script shows how to get the list of subports from a portfile:
>> 
>> https://trac.macports.org/browser/contrib/mp-buildbot/tools/subports.tcl
>> 
>> However it does this by using mportinfo, and it doesn't look like mportinfo contains information on the supported archs.
>> 
>> Any ideas?
> 
> You can use _mportkey to get the value of any variable from the Portfile interpreter.

Thanks!