有一种非常方便的工具，即命令行应用程序FFmpeg。
One particularly handy tool for doing that is a command-line application called FFmpeg.
捕获用户与命令行应用程序的交互不只是一个写数据的任务。
Capturing a user's interaction with a command-line application is not just a writing task.
GShell是一个用于构建丰富的命令行应用程序的框架。
GShell is a framework for building rich command line applications.
应用推荐