+
+ # if we pipe fron STDIN, open3 closes STDIN, so we we
+ # a perl warning "Filehandle STDIN reopened as GENXYZ .. "
+ # as soon as we open a new file.
+ # to avoid that we open /dev/null
+ if (!ref($writer) && !defined(fileno(STDIN))) {
+ POSIX::close(0);
+ open(STDIN, "</dev/null");
+ }