- if (options->output_prefix) {
- struct strbuf *msg = NULL;
- msg = options->output_prefix(options,
- options->output_prefix_data);
- fwrite(msg->buf, msg->len, 1, stdout);
- }
- putc(options->line_termination, options->file);
+ fprintf(options->file, "%s%c",
+ diff_line_prefix(options),
+ options->line_termination);