#include <stdbool.h>
#include <stddef.h>
+/* The following #include avoids a potential problem when Gnulib substitutes
+ * for close() by putting "#define close rpl_close" into <unistd.h>, by
+ * ensuring that every source file that includes this one sees the #define.
+ * (It would probably be better to rename the 'close' member of struct
+ * lex_reader_class.) */
+#include <unistd.h>
+
#include "data/identifier.h"
#include "data/variable.h"
#include "libpspp/compiler.h"