+/** Variable String N PRINT Formatted. Equivalent to vsprintf( dest, format,
+ * args ), but will not write more than n characters.
+ * @param dest The char array to write to.
+ * @param n Maximum number of characters to write.
+ * @param format The formatting string.
+ * @param args The argument list created by the va_start macro.
+ * @return Number of characters printed.
+ */
+int vsnprintf( char * restrict dest, size_t n, const char * restrict format, va_list ap );
+
+/* ------------------------------------------------------------------------- */
+
+/** Print ERROR.
+ * Equivalent to fprintf( stderr, "%s: %s\n", text, strerror( errno ) ).
+ * @param test Text to prepend the error message with.
+ */
+void perror( const char * text );
+
+/* ------------------------------------------------------------------------- */
+
+/** File READ. Reads a number of objects of a given size from file, and into
+ * a memory area.
+ * @param dest The memory area to write into.
+ * @param size The size of one object.
+ * @param n The number of objects to read.
+ * @param fh The file handle.
+ * @return The number of objects successfully read.
+ */
+size_t fread( void * restrict dest, size_t size, size_t n, FILE * restrict fh );
+
+/** File WRITE. Writes a number of objects from a memory area to file.
+ * @param src The memory area to write from.
+ * @param size The size of a single object.
+ * @param n The number of objects to write.
+ * @param fh The file handle.
+ * @return The number of objects successfully written.
+ */
+size_t fwrite( const void * restrict src, size_t size, size_t n, FILE * restrict fh );
+
+/* ------------------------------------------------------------------------- */
+
+/** SET Virtual BUFfer. Sets buffering mode and (optionally) the memory used
+ * for buffering, for a given file handle.
+ * This function must only be called immediately after associating the file
+ * handle with a file, before any operations are called on the file handle.
+ * @param fh The file handle.
+ * @param buf A pointer to the memory area to use for buffering, or NULL to
+ * use internally assigned buffer memory.
+ * @param mode One of _IOFBF, _IOLBF, _IONBF.
+ * @param size Size of the memory area to be used for buffering.
+ */
+int setvbuf( FILE * restrict fh, char * restrict buf, int mode, size_t size );
+
+/** SET BUFfer. Equivalent to (void) setvbuf( fh, buf, _IOFBF, BUFSIZ ), or
+ * (void) setvbuf( fh, NULL, _IONBF, BUFSIZ ) if buf == NULL.
+ * @param fh The file handle to be passed to setvbuf().
+ * @param buf The buffer pointer to be passed to setvbuf().
+ */
+void setbuf( FILE * restrict fh, char * restrict buf );
+
+/* ------------------------------------------------------------------------- */
+