当stdout被用于输出二进制数据时，如何还能将debug/verbose信息输出到终端?

I'm writing an application that will open a file and output some processed version. It will be a graphical desktop application, but must also be suitable for running on a web server. It therefore needs to provide a suitable interface for a web app's back-end code (which will likely be PHP).I'm writing an application that will open a fil