--- io.c.orig	Tue Nov 29 16:08:20 2016
+++ io.c	Tue Nov 29 16:09:40 2016
@@ -38,7 +38,7 @@
 #endif
 
 #ifndef BSD_STDIO
-# if defined(__MACH__) || defined(__DARWIN__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__bsdi__)
+# if defined(__MACH__) || defined(__DARWIN__) || defined(__FreeBSD__) || defined(__minix) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__bsdi__)
 #   define BSD_STDIO 1
 # else
 #   define BSD_STDIO 0
@@ -1308,7 +1308,7 @@
         }
         if (fptr->f) { /* update pos in FILE structure [ruby-core:21561] */
             fflush(fptr->f);
-#if defined(__SOFF) && defined(__NetBSD__)
+#if defined(__SOFF) && (defined(__minix) || defined(__NetBSD__))
 	    fptr->f->_flags &= ~__SOFF;
 	    (void)io_tell(fptr);
 #endif