cmd/gio: rename -v to -x and add -work

The verbose flag only triggered printing of commands, which is
traditionally named -x by other Go tools.

The -work flag will print and preserve the temporary directory.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

cmd/gio/gio.go

@@ -19,7 +19,8 @@ var (
 	buildMode     = flag.String("buildmode", "exe", "specify buildmode: archive or exe")
 	destPath      = flag.String("o", "", "output file (Android .aar or .apk file) or directory (iOS/tvOS .framework or webassembly files)")
 	appID         = flag.String("appid", "org.gioui.app", "app identifier (for -buildmode=exe)")
-	verbose   = flag.Bool("v", false, "verbose output")
+	printCommands = flag.Bool("x", false, "print the commands")
+	keepWorkdir   = flag.Bool("work", false, "print the name of the temporary work directory and do not delete it when exiting.")
 )
 
 type buildInfo struct {
@@ -89,7 +90,11 @@ func build(bi *buildInfo) error {
 	if err != nil {
 		return err
 	}
+	if *keepWorkdir {
+		fmt.Fprintf(os.Stderr, "WORKDIR=%s\n", tmpDir)
+	} else {
 		defer os.RemoveAll(tmpDir)
+	}
 	switch *target {
 	case "js":
 		return buildJS(bi)
@@ -108,7 +113,7 @@ func errorf(format string, args ...interface{}) {
 }
 
 func runCmdRaw(cmd *exec.Cmd) ([]byte, error) {
-	if *verbose {
+	if *printCommands {
 		fmt.Printf("%s\n", strings.Join(cmd.Args, " "))
 	}
 	out, err := cmd.Output()