streamdefs.h
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/*ident "@(#)cls4:lib/stream/streamdefs.h 1.3" */
/*******************************************************************************
C++ source for the C++ Language System, Release 3.0. This product
is a new release of the original cfront developed in the computer
science research center of AT&T Bell Laboratories.
Copyright (c) 1993 UNIX System Laboratories, Inc.
Copyright (c) 1991, 1992 AT&T and UNIX System Laboratories, Inc.
Copyright (c) 1984, 1989, 1990 AT&T. All Rights Reserved.
THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE of AT&T and UNIX System
Laboratories, Inc. The copyright notice above does not evidence
any actual or intended publication of such source code.
*******************************************************************************/
// This file contains #defines for controlling conditional compilation
// of the stream library
// The follwing functions adjust for machine dependencies
#define BREAKEVEN 10
/* The approximate length of a string
* for which it is faster to do a strncpy
* than a char by char loop. If BREAKEVEN is 0
* then strncpy is always better. If it is <0 then
* loop is always better, (e.g. if strncopy does
* a char by char copy anyway.)
*/
#define SEEK_ARITH_OK 1
/* System supports arithmetic on stream positions.
* I.e. if file is at a position and we read or
* write n bytes we can find the new position
* by adding n to old position. (Providing
* O_APPEND isn't set in on open.)
*/
static const int PTRBASE = ios::hex ;
/* base for output of pointers (void*) */
// There is one important machine dependent feature of this implementation
// It assumes that it can always create a pointer to the byte after
// a char array used as a buffer, and that pointer will be greater than
// any pointer into the array.
// My reading of the ANSI standard is that this assumption is permissible,
// but I can imagine segmented architectures where it fails.
/* #define VSPRINTF vsprintf */
/* If defined, the name of a "vsprintf" function.
* If not defined,
* various non-portable kludges are used in
* oldformat.c
*/
static const int STREAMBUFSIZE = 1024 ;
// The default buffer size.
/*******
#define O_CREAT 01000
#define O_TRUNC 02000
#define O_EXCL 04000
*******/
/* Used in filebuf.c. Define if your system
* needs it to have a value different from
* that indicated here, but doesn't
* define it in standard system headers
*/
/****
#define STDIO_ONLY
****/
/* If STDIO_ONLY is defined, then filebuf.c
* will be compiled to only use stdio functions.
* This does not provide complete functionality
* (e.g. some open modes are not supported), but
* is a way to port iostreams to non UNIX
* environments.
*/