Multilevel SDK Lookup

[cakine]

.NETCore activation will look for the SDK version folder in the current working directory, the user location, the executable directory and the global .NET location, in the order described.

The user and global locations are defined as follows:

User location:
Windows 32-bit: %SystemDrive%\Users\username.dotnet\x86
Windows 64-bit: %SystemDrive%\Users\username.dotnet\x64
Unix 32-bit: /home/username/.dotnet/x86
Unix 64-bit: /home/username/.dotnet/x64

Global location:
Windows 32-bit: %SystemDrive%\Program Files\dotnet
Windows 64-bit (32-bit application): %SystemDrive%\Program Files (x86)\dotnet
Windows 64-bit (64-bit application): %SystemDrive%\Program Files\dotnet
Unix: the directory of “dotnet” defined in the system path.

[dnfclas]

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[cakine]

@gkhanna79 @ramarag

[gkhanna79]

Looks good modulo a refactoring comment. Please update the PR for that.

[eerhardt]

Unix: the directory of “dotnet” defined in the system path.

I consider this policy to be wrong. Just because a command is in my path, doesn't mean that it should affect other commands. %ProgramFiles% on Windows != $PATH on Unix.

Take for example two machines: one that does and one that doesn't have dotnet in $PATH. Everything else being equal, my app could execute just fine on the machine with some other dotnet on the $PATH. I then publish my app, and move it to another machine, all of a sudden the app breaks because there isn't a dotnet on the $PATH.

[gkhanna79]

all of a sudden the app breaks because there isn't a dotnet on the $PATH.

I do not think the app should break if there is no dotnet on path - it should only result in us determining that there is no global location for dotnet installation.

This change is implemented at
https://github.com/dotnet/core-setup/blob/master/src/corehost/common/pal.unix.cpp#L237 and was so since day 1 because there is no equivalent of PF folder on Unix to determine "global" locations. This is simply used as hint for it.

[cakine]

I'll merge the changes tomorrow (Feb. 22nd) if there are no more concerns.

[gkhanna79]

Ubuntu Arm release failure is unrelated. Merging the PR.