chore(all): make code compilable for other platforms than Linux

internal/openvpn/start.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"os/exec"
-	"syscall"
 
 	"github.com/qdm12/gluetun/internal/constants/openvpn"
 )
@@ -33,7 +32,7 @@ func start(ctx context.Context, starter CmdStarter, version string, flags []stri
 	args := []string{"--config", configPath}
 	args = append(args, flags...)
 	cmd := exec.CommandContext(ctx, bin, args...)
-	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
+	setCmdSysProcAttr(cmd)
 
 	return starter.Start(cmd)
 }

internal/openvpn/start_linux.go

@@ -0,0 +1,10 @@
+package openvpn
+
+import (
+	"os/exec"
+	"syscall"
+)
+
+func setCmdSysProcAttr(cmd *exec.Cmd) {
+	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
+}

internal/openvpn/start_unspecified.go

@@ -0,0 +1,12 @@
+//go:build !linux
+
+package openvpn
+
+import (
+	"os/exec"
+	"syscall"
+)
+
+func setCmdSysProcAttr(cmd *exec.Cmd) {
+	cmd.SysProcAttr = &syscall.SysProcAttr{}
+}