用于Linux平台下读写PDF文件的接口，运行在X-Windows环境。该模块还包含了PDF 文本提取，PDF-to-Postscr ipt转换-For the Linux platform interface to read and write PDF files, to run in the X-Windows environment. The module also includes a PDF text extraction, PDF-to-Postscr ipt conversion

How to Kill and Restart X Windows in Linux Environment: detailed explanation