Index: include/stdio.h
===================================================================
--- include/stdio.h
+++ include/stdio.h
@@ -302,7 +302,16 @@
 
 char	*ctermid(char *);
 FILE	*fdopen(int, const char *);
+#ifndef FILENO_C
+#if defined(__STDC_VERSION__)
+/* C95 compatible source code. */
+static inline int	 fileno(FILE *);
+#else
+/* defined(__ANSI__) || defined(__cplusplus) */
+/* C89 compatible source code. for C89 we DONT HAVE 'inline' keyword and for C++ we dont need static inline one (as not defined :D) */
 int	 fileno(FILE *);
+#endif
+#endif
 #endif /* __POSIX_VISIBLE */
 
 #if __POSIX_VISIBLE >= 199209
@@ -328,8 +337,17 @@
 void	 clearerr_unlocked(FILE *);
 int	 feof_unlocked(FILE *);
 int	 ferror_unlocked(FILE *);
+#ifndef FILENO_C
+#if defined(__STDC_VERSION__)
+/* C95 compatible source code. */
+static inline int	 fileno_unlocked(FILE *);
+#else
+/* defined(__ANSI__) || defined(__cplusplus) */
+/* C89 compatible source code. for C89 we DONT HAVE 'inline' keyword and for C++ we dont need static inline one (as not defined :D) */
 int	 fileno_unlocked(FILE *);
 #endif
+#endif
+#endif
 
 #if __POSIX_VISIBLE >= 200112
 int	 fseeko(FILE *, __off_t, int);
@@ -495,8 +513,21 @@
 #define	clearerr(p)	(!__isthreaded ? __sclearerr(p) : (clearerr)(p))
 
 #if __POSIX_VISIBLE
+#ifndef FILENO_C
+#if defined(__STDC_VERSION__)
+/* C95 compatible source code. */
+static inline int
+fileno(FILE *p)
+{
+	return (!__isthreaded ? __sfileno(p) : (fileno)(p));
+}
+#else
+/* defined(__ANSI__) but here we are sure !defined(__cplusplus) :D */
+/* C89 compatible source code. for C89 we DONT HAVE 'inline' keyword */
 #define	fileno(p)	(!__isthreaded ? __sfileno(p) : (fileno)(p))
 #endif
+#endif
+#endif
 
 #define	getc(fp)	(!__isthreaded ? __sgetc(fp) : (getc)(fp))
 #define	putc(x, fp)	(!__isthreaded ? __sputc(x, fp) : (putc)(x, fp))
@@ -512,8 +543,21 @@
 #define	feof_unlocked(p)	__sfeof(p)
 #define	ferror_unlocked(p)	__sferror(p)
 #define	clearerr_unlocked(p)	__sclearerr(p)
+#ifndef FILENO_C
+#if defined(__STDC_VERSION__)
+/* C95 compatible source code. */
+static inline int
+fileno_unlocked(FILE *p)
+{
+	return __sfileno(p);
+}
+#else
+/* defined(__ANSI__) but here we are sure !defined(__cplusplus) :D */
+/* C89 compatible source code. for C89 we DONT HAVE 'inline' keyword */
 #define	fileno_unlocked(p)	__sfileno(p)
 #endif
+#endif
+#endif
 #if __POSIX_VISIBLE >= 199506
 #define	getc_unlocked(fp)	__sgetc(fp)
 #define	putc_unlocked(x, fp)	__sputc(x, fp)
Index: lib/libc/stdio/fileno.c
===================================================================
--- lib/libc/stdio/fileno.c
+++ lib/libc/stdio/fileno.c
@@ -37,6 +37,7 @@
 __FBSDID("$FreeBSD$");
 
 #include "namespace.h"
+#define FILENO_C
 #include <stdio.h>
 #include "un-namespace.h"
 #include "libc_private.h"
@@ -62,3 +63,4 @@
 
 	return (__sfileno(fp));
 }
+#undef FILENO_C