`--enable-write18`

  Fully enable the \write18{command} construct. It is only partially enabled by default to avoid security problems. When fully enabled, the command (which undergoes the usual &TeX; expansions) is passed to the command interpreter. The output of the command is not diverted anywhere, so it will not appear in the log file. The command execution either happens at \output time or right away, according to the absence or presence of the \immediate prefix.

--enable-write18
--shell-escape
\write18 (run a program from within &TeX;)