Officially remove OpenBSD support

Because we cannot fix the CI issue on OpenBSD and we cannot support it.
In case, we keep the code for OpenBSD but it is not tested and we cannot
guarantee its correctness.

See #65

Author: lambdalisue

.github/workflows/test.yml

@@ -113,11 +113,6 @@ jobs:
               version: "14.1",
               prepare_cmd: "sudo pkg install -y rust cmake rust-bindgen-cli",
             }
-          - {
-              os: openbsd,
-              version: "7.6",
-              prepare_cmd: "sudo pkg_add rust cmake llvm%17; export LIBCLANG_PATH=/usr/local/llvm17/lib",
-            }
       fail-fast: false
     runs-on: ubuntu-latest
     name: "test (${{matrix.os}}-${{matrix.version}})"

README.md

@@ -8,10 +8,9 @@
 # ⏱ metrics-process
 
 This crate provides a [Prometheus]-style [process metrics] collector for the
-[metrics] crate, supporting Linux, macOS, Windows, FreeBSD, and OpenBSD. The
-original collector code was manually rewritten in Rust from the official
-Prometheus client for Go ([client_golang]), \*BSD support code was written
-from scratch.
+[metrics] crate, supporting Linux, macOS, Windows, and FreeBSD. The original
+collector code was manually rewritten in Rust from the official Prometheus
+client for Go ([client_golang]), \*BSD support code was written from scratch.
 
 [Prometheus]: https://prometheus.io/
 [process metrics]: https://prometheus.io/docs/instrumenting/writing_clientlibs/#process-metrics
@@ -35,29 +34,32 @@ This crate supports the following metrics provided by [Prometheus] for
 | `process_threads`                  | Number of OS threads in the process.                       |
 
 For each platform, it is equivalent to what the official Prometheus client for
-Go ([client_golang]) provides.
+Go ([client_golang]) provides. Note that code for OpenBSD exists but is not
+tested and we cannot guarantee its correctness.
 
 > [!NOTE]
 >
-> Prior to version 2.0.0, the `process_cpu_seconds_total` metric was Gauge instead of Counter.
-> Enable `use-gauge-on-cpu-seconds-total` feature to use the previous behavior.
-
-| Metric name                        | Linux | macOS | Windows | FreeBSD | OpenBSD |
-| ---------------------------------- | ----- | ----- | ------- | ------- | ------- |
-| `process_cpu_seconds_total`        | x     | x     | x       | x       | x       |
-| `process_open_fds`                 | x     | x     | x       | x       |         |
-| `process_max_fds`                  | x     | x     | x       | x       | x       |
-| `process_virtual_memory_bytes`     | x     | x     | x       | x       |         |
-| `process_virtual_memory_max_bytes` | x     | x     |         | x       |         |
-| `process_resident_memory_bytes`    | x     | x     | x       | x       | x       |
-| `process_heap_bytes`               |       |       |         |         |         |
-| `process_start_time_seconds`       | x     | x     | x       | x       | x       |
-| `process_threads`                  | x     | x     |         | x       |         |
+> Prior to version 2.0.0, the `process_cpu_seconds_total` metric was Gauge
+> instead of Counter. Enable `use-gauge-on-cpu-seconds-total` feature to use the
+> previous behavior.
+
+| Metric name                        | Linux | macOS | Windows | FreeBSD | (OpenBSD) |
+| ---------------------------------- | ----- | ----- | ------- | ------- | --------- |
+| `process_cpu_seconds_total`        | x     | x     | x       | x       | x         |
+| `process_open_fds`                 | x     | x     | x       | x       |           |
+| `process_max_fds`                  | x     | x     | x       | x       | x         |
+| `process_virtual_memory_bytes`     | x     | x     | x       | x       |           |
+| `process_virtual_memory_max_bytes` | x     | x     |         | x       |           |
+| `process_resident_memory_bytes`    | x     | x     | x       | x       | x         |
+| `process_heap_bytes`               |       |       |         |         |           |
+| `process_start_time_seconds`       | x     | x     | x       | x       | x         |
+| `process_threads`                  | x     | x     |         | x       |           |
 
 > [!NOTE]
 >
-> If you only need to compile this crate on non-supported platforms, you can use the `dummy` feature.
-> Enabling this feature activates a dummy collector, which returns an empty `Metrics`.
+> If you only need to compile this crate on non-supported platforms, you can use
+> the `dummy` feature. Enabling this feature activates a dummy collector, which
+> returns an empty `Metrics`.
 
 [client_golang]: https://github.com/prometheus/client_golang