[NTG-pdftex] Patch ShellEscape

Heiko Oberdiek oberdiek@uni-freiburg.de
Thu, 5 Jun 2003 21:44:45 +0200

Patch ShellEscape

Packages such as pdftricks.sty, epstopdf.sty (or pdftex.def)
call external programs. They do not work at all, if the
\write18 feature is not enabled. Therefore a robust method
would be useful in order to inform the user. For security
reasons the \write18 featuer must not be set by TeX macro
  Thus the patch introduces a new readonly primitive
\pdfshellescape that expands to "0" if the \write 18 feature
is disabled and "1" in the other case.

Use, for instance:

  \message{The \string\write18 feature is disabled.}
  \message{The \string\write18 feature is enabled.}

Patch files:
  pdftex.ch.diff   for TeX/texk/web2c/pdftexdir/pdftex.ch
  pdfetex.ch2.diff for TeX/texk/web2c/pdfetexdir/pdfetex.ch2

Yours sincerely
  Heiko <oberdiek@uni-freiburg.de>