+dnl
+dnl Checks for _IO_write_ptr. A Linuxism used by nmh on linux. We
+dnl really use a whole set of them, but this check should be
+dnl sufficient.
+dnl
+AC_CHECK_HEADER(libio.h, [
+ AC_EGREP_HEADER(_IO_write_ptr, libio.h, [
+ AC_DEFINE(LINUX_STDIO,1,[Use the Linux _IO_*_ptr defines from <libio.h>.]) ]) ])
+