Creates a temp file directly and uses that rather than just a path

internal/driver/fetch.go

 	ui.Print(fmt.Sprintf(
 		"Converting %s to a profile.proto... (May take a few minutes)",
 		perfPath))
-	profilePath, err := newTempFilePath("/tmp", "pprof_", ".pb.gz")
+	profile, err := newTempFile("/tmp", "pprof_", ".pb.gz")
 	if err != nil {
 		return nil, err
 	}
-	cmd := exec.Command("perf_to_profile", perfPath, profilePath)
-	// If perf_to_profile failed before generating the file, this defer
-	// is just a no-op.
-	deferDeleteTempFile(profilePath)
+	deferDeleteTempFile(profile.Name())
+	cmd := exec.Command("perf_to_profile", perfPath, profile.Name())
 	if err := cmd.Run(); err != nil {
+		profile.Close()
 		return nil, err
 	}
-	return os.Open(profilePath)
+	return profile, nil
 }
 
 // adjustURL validates if a profile source is a URL and returns an

internal/driver/tempfile.go

 	"sync"
 )
 
-// newTempFilePath returns an unused path for output files.
-func newTempFilePath(dir, prefix, suffix string) (string, error) {
+// newTempFile returns a new output file in dir with the provided prefix and suffix.
+func newTempFile(dir, prefix, suffix string) (*os.File, error) {
 	for index := 1; index < 10000; index++ {
 		path := filepath.Join(dir, fmt.Sprintf("%s%03d%s", prefix, index, suffix))
 		if _, err := os.Stat(path); err != nil {
-			return path, nil
+			return os.Create(path)
 		}
 	}
 	// Give up
-	return "", fmt.Errorf("could not create file of the form %s%03d%s", prefix, 1, suffix)
-}
-
-// newTempFile returns a new file with a random name for output files.
-func newTempFile(dir, prefix, suffix string) (*os.File, error) {
-	path, err := newTempFilePath(dir, prefix, suffix)
-	if err != nil {
-		return nil, err
-	}
-	return os.Create(path)
+	return nil, fmt.Errorf("could not create file of the form %s%03d%s", prefix, 1, suffix)
 }
 
 var tempFiles []string