Unable To Compile Google Protobuf 2 Messages using C# with Mono

Question

i am using protobuf and c#, and the c# port seems to be the answer for generating c# classes using proto2. i was able to figure out that the c# port was built with dotnet 2.0 from this SO post, and i am using mono latest, which is 4.4.x at the time of writing. my command is:

mono ./ProtoGen.exe --proto_path=../idl -output_directory=../out ../my.proto

it yields

WARNING: The runtime version supported by this application is unavailable.
Using default runtime: v4.0.30319

no files are output, and echo $? tells me it exited with 255.

any tips? thanks!

Answer 1

It is a little buried in the current protobuf v3.0 documentation, however, it is there under the Compiler Invocation section.

Only proto3 messages are supported by the C# code generator. Ensure that each .proto file begins with a declaration of:

syntax = "proto3";