use ubuntu server cli to convert dwg to pdf

hello is it possible to get export of dwg file to pdf in ubuntu cli with librecad? i installed librecad but get this error:
peiman@server:~$ librecad --convert 1.dwg 2.pdf
RS_DEBUG::setLevel(3)
RS_DEBUG: Critical
RS_DEBUG: Errors
RS_DEBUG: Warnings
QXcbConnection: Could not connect to display
Aborted (core dumped)

Hi pieman,

Where did you find that '--convert' option? LibreCAD does not have one. LibreCAD can convert a drawing to pdf file from cli, but only in dxf (not dwg) format. If you can convert your dwg to dxf first then you can use LibreCAD's dxf2pdf tool. Its help is available by running

./librecad dxf2pdf --help

But if you need to run it on server where X is not running, may be this link can help you: LibreCAD_dxf2pdf_standalone