[MacPorts] #39083: Add information about configure.sdkroot and macosx_deployment_target (was: Add information about configure.sdkroot and configure.macosx_deployment_target)

[MacPorts]

#39083: Add information about configure.sdkroot and macosx_deployment_target
--------------------------+----------------------
  Reporter:  gallafent    |      Owner:  mascguy
      Type:  enhancement  |     Status:  assigned
  Priority:  Normal       |  Milestone:
 Component:  guide        |    Version:
Resolution:               |   Keywords:
      Port:               |
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Old description:

> At present the guide has only a placeholder for the
> configure.macosx_deployment_target and related variables, and no mention
> at all of configure.sdkroot.
>
> It would be very useful if these (and any others that are missing) had
> /at least/ placeholders (even without any meaningful documentation), so
> that they may be discovered. I recently /guessed/ at the existence of the
> configure.sdkroot variable, and this was exactly what I needed to use to
> get round a problem while testing a port which didn't compile! It would
> have been quicker if I could have seen it somewhere in the guide.
>
> Also, an explanation of how to discover the list of valid variables
> directly from an installed port tree (for use when the documentation is
> outdated) would also be helpful.

New description:

 At present the guide has only a placeholder for `macosx_deployment_target`
 and related variables, and no mention at all of `configure.sdkroot`.

 It would be very useful if these (and any others that are missing) had /at
 least/ placeholders (even without any meaningful documentation), so that
 they may be discovered. I recently /guessed/ at the existence of the
 `configure.sdkroot` variable, and this was exactly what I needed to use to
 get round a problem while testing a port which didn't compile! It would
 have been quicker if I could have seen it somewhere in the guide.

 Also, an explanation of how to discover the list of valid variables
 directly from an installed port tree (for use when the documentation is
 outdated) would also be helpful.

--

Comment (by mascguy):

 Update as of this writing:

 * `configure.sdkroot` is documented in the guide, but missing from the
 manpage for `portfile`.
 * `macosx_deployment_target` is documented in the manpage, but missing
 from the guide.

-- 
Ticket URL: <https://trac.macports.org/ticket/39083#comment:4>
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