Standard I/O Packages - GNAT Reference Manual

Next: FORM Strings, Up: The Implementation of Standard I/O

8.1 Standard I/O Packages

The Standard I/O packages described in Annex A for

Ada.Text_IO
Ada.Text_IO.Complex_IO
Ada.Text_IO.Text_Streams
Ada.Wide_Text_IO
Ada.Wide_Text_IO.Complex_IO
Ada.Wide_Text_IO.Text_Streams
Ada.Wide_Wide_Text_IO
Ada.Wide_Wide_Text_IO.Complex_IO
Ada.Wide_Wide_Text_IO.Text_Streams
Ada.Stream_IO
Ada.Sequential_IO
Ada.Direct_IO

are implemented using the C library streams facility; where

All files are opened using fopen.
All input/output operations use fread/fwrite.

There is no internal buffering of any kind at the Ada library level. The only buffering is that provided at the system level in the implementation of the C library routines that support streams. This facilitates shared use of these streams by mixed language programs.