Difference between – and -​- in compiling options-Collection of common programming errors

-shell=escape is invalid.

The correct syntax is the one starting with two hyphens. The versions with one hyphen (-shell-escape) often works too. But as Christian Schenk, the maintainer of MiKTeX, once wrote:

Please note that the single ‘-‘ prefixes a sequence of single-letter options (aka short options). That is, if you specify -unre, you are actually invoking these options:

--update-fndb  --print-only  --user-roots

I would recommend, tha you always specify the “long options” (prefixed by two ‘-‘). The short options (one ‘-‘) are only for backward compatibility.

Originally posted 2013-11-09 21:44:38.