Inkscape comes with a command line interface for scripting various commands.
To export an Inkscape SVG file image.svg to a PDF image.pdf, we can use the
following command
inkscape --file=image.svg --without-gui --export-pdf=image.pdf
Check the man page for alternative file types.
By default, this renders all drawn elements in the SVG to the PDF, rather than
the selected page area. To render only the page selected in Inkscape, add the flag --export-area-page.