libreoffice --headless --convert-to pdf --outdir /tmp ~/word.docx 报错： Failed to open display /usr/lib64/libreoffice/program/soffice.bin X11 error: Can't open display: Set DISPLAY environment variable, use -display option or check permissions of your X-Server (See "man X" resp. "man xhost" for details) 解决方法： yum install libreoffice-headless