程式語言 - X11-Basic - 解決no images defined x11basic.svg問題

問題如下：

convert  x11basic.eps x11basic.svg
convert-im6.q16: attempt to perform an operation not allowed by the security policy `PS' @ error/constitute.c/IsCoderAuthorized/426.
convert-im6.q16: no images defined `x11basic.svg' @ error/convert.c/ConvertImageCommand/3229.
make: *** [Makefile:601: x11basic.svg] Error 1

解法如下：

$ sudo apt install potrace ghostscript
$ sudo vim /etc/ImageMagick-6/policy.xml
    <!-- disable ghostscript format types -->
    <policy domain="coder" rights="read|write" pattern="PS" />
    <policy domain="coder" rights="read|write" pattern="PS2" />
    <policy domain="coder" rights="read|write" pattern="PS3" />
    <policy domain="coder" rights="read|write" pattern="EPS" />
    <policy domain="coder" rights="read|write" pattern="PDF" />
    <policy domain="coder" rights="read|write" pattern="XPS" />