@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990-1994, 1998-1999, 2001-2014 Free Software
+@c Copyright (C) 1990-1994, 1998-1999, 2001-2016 Free Software
@c Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@node Read and Print
When it is called with one argument (always a character), @var{function}
should save the argument and arrange to return it on the next call.
This is called @dfn{unreading} the character; it happens when the Lisp
-reader reads one character too many and wants to ``put it back where it
-came from''. In this case, it makes no difference what value
+reader reads one character too many and wants to put it back where it
+came from. In this case, it makes no difference what value
@var{function} returns.
@end itemize
@code{t}.
@end defvar
+@cindex binary I/O in batch mode
+When reading or writing from the standard input/output streams of the
+Emacs process in batch mode, it is sometimes required to make sure any
+arbitrary binary data will be read/written verbatim, and/or that no
+translation of newlines to or from CR-LF pairs is performed. This
+issue does not exist on Posix hosts, only on MS-Windows and MS-DOS@.
+The following function allows you to control the I/O mode of any
+standard stream of the Emacs process.
+
+@defun set-binary-mode stream mode
+Switch @var{stream} into binary or text I/O mode. If @var{mode} is
+non-@code{nil}, switch to binary mode, otherwise switch to text mode.
+The value of @var{stream} can be one of @code{stdin}, @code{stdout},
+or @code{stderr}. This function flushes any pending output data of
+@var{stream} as a side effect, and returns the previous value of I/O
+mode for @var{stream}. On Posix hosts, it always returns a
+non-@code{nil} value and does nothing except flushing pending output.
+@end defun
+
@node Output Streams
@section Output Streams
@cindex stream (for printing)
@defun pp object &optional stream
This function outputs @var{object} to @var{stream}, just like
-@code{prin1}, but does it in a more ``pretty'' way. That is, it'll
+@code{prin1}, but does it in a prettier way. That is, it'll
indent and fill the object to make it more readable for humans.
@end defun
+If you need to use binary I/O in batch mode, e.g., use the functions
+described in this section to write out arbitrary binary data or avoid
+conversion of newlines on non-Posix hosts, see @ref{Input Functions,
+set-binary-mode}.
+
@node Output Variables
@section Variables Affecting Output
@cindex output-controlling variables