opentelemetry-cpp

These do not seem to be pure "header-only", but involve #include-ing the same file at least once with "#define C2_xxx_IMPLEMENTATION 1" That's fine though. AFAIK, there is no sane way (across platforms) to have singletons, and that involves some of the the trick above, unless you know someother way If you do, please add your idea here - https://github.com/open-telemetry/opentelemetry-cpp/issues/2... - "Header only singletons are not working properly for Windows #2534"

It's 8mb dll when compiled fully as dll(s). Check the https://github.com/open-telemetry/opentelemetry-cpp as they've recently added dll support, and I've been keeping a branch that's geared towards more simplicity on deploy (e.g. single .dll, instead of several) - OpenTelemetry's C++ solution though is more flexible, and less size used last I've tried it. Here is mine - https://github.com/malkia/opentelemetry-cpp

Maybe surprisingly, there doesn't seem to be an open source C client library for OpenTelemetry at the moment -- I'd guess that such a library would make introducing spans/traces in PostgreSQL a bit easier (although to be honest, I don't know/remember much about calling and linking to C++ libraries from a C codebase). (note: there is a C++ client[1], although they mention that support for C is not currently[2] a goal of the project -- and I couldn't find any C implementations elsewhere) [1] - https://github.com/open-telemetry/opentelemetry-cpp.git/ [2] - https://github.com/open-telemetry/opentelemetry-cpp/tree/db6...