fixup! Attempt to pick the fastest network interface for workers

Author: JamesWrigley

src/network_interfaces.jl

@@ -1,4 +1,4 @@
-## This is a minimal version of NetworkInterfaceControllers.jl
+## This is a minimal version of NetworkInterfaceControllers.jl, licensed under MIT
 
 # uv_interface_address_t has a few fields, but we don't support accessing all of
 # them because `name` is the first field and it's a pointer:
@@ -97,29 +97,34 @@ function _get_interfaces(
             (:skip, nothing)
         end
 
-        # Load sysfs info
-        sysfs_path = "/sys/class/net/$(name)"
-        type_path = "$(sysfs_path)/type"
-        speed_path = "$(sysfs_path)/speed"
         type = nothing
-        if isfile(type_path)
-            try
-                type_code = parse(Int, read(type_path, String))
-                if type_code in Int.(instances(ARPHardware))
-                    type = ARPHardware(type_code)
+        speed = nothing
+
+        @static if Sys.isunix()
+            # Load sysfs info
+            sysfs_path = "/sys/class/net/$(name)"
+            type_path = "$(sysfs_path)/type"
+            speed_path = "$(sysfs_path)/speed"
+
+            if isfile(type_path)
+                try
+                    type_code = parse(Int, read(type_path, String))
+                    if type_code in Int.(instances(ARPHardware))
+                        type = ARPHardware(type_code)
+                    end
+                catch
+                    # Do nothing on any failure to read or parse the file
                 end
-            catch
-                # Do nothing on any failure to read or parse the file
             end
-        end
-        speed = nothing
-        if isfile(speed_path)
-            try
-                reported_speed = parse(Float64, read(speed_path, String))
-                if reported_speed > 0
-                    speed = reported_speed
+
+            if isfile(speed_path)
+                try
+                    reported_speed = parse(Float64, read(speed_path, String))
+                    if reported_speed > 0
+                        speed = reported_speed
+                    end
+                catch
                 end
-            catch
             end
         end