diff --git a/libc/stdio/wbuf.c b/libc/stdio/wbuf.c
index c757799..e09ac59 100644
--- a/libc/stdio/wbuf.c
+++ b/libc/stdio/wbuf.c
@@ -65,20 +65,20 @@
 	 * stuff c into the buffer.  If this causes the buffer to fill
 	 * completely, or if c is '\n' and the file is line buffered,
 	 * flush it (perhaps a second time).  The second flush will always
-	 * happen on unbuffered streams, where _bf._size==1; fflush()
+	 * happen on unbuffered streams, where _bf._size==1; __sflush()
 	 * guarantees that putc() will always call wbuf() by setting _w
 	 * to 0, so we need not do anything else.
 	 */
 	n = fp->_p - fp->_bf._base;
 	if (n >= fp->_bf._size) {
-		if (fflush(fp))
+		if (__sflush(fp))
 			return (EOF);
 		n = 0;
 	}
 	fp->_w--;
 	*fp->_p++ = c;
 	if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n'))
-		if (fflush(fp))
+		if (__sflush(fp))
 			return (EOF);
 	return (c);
 }