On Jul 13, 2019, at 11:22, dan d. wrote: > I have recently started geting these error messages when attempting upgrades, > what do they mean and how can I fix the problem? > Error: Unable to determine location of a macOS SDK. > Error: Unable to open port: can't read "configure.sdkroot": Unable to > determine location of a macOS SDK.
What version of macOS and Xcode are you using and do you also have the command line tools installed? Do you see this message with every port or only certain ports? (Which ports?)
