/* This file is the configuration file for the Linux operating system.
   Copyright (C) 1985, 1986, 1992, 1994 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* This file was put together by Michael K. Johnson and Rik Faith.  */


/*
 *	Define symbols to identify the version of Unix this is.
 *	Define all the symbols that apply correctly.
 */

/* #define UNIPLUS */
/* #define USG5 */
#define USG
/* #define BSD */
#define LINUX

/* SYSTEM_TYPE should indicate the kind of system you are using.
 It sets the Lisp variable system-type.  */

#define SYSTEM_TYPE "linux"		/* All the best software is free. */

/* Emacs can read input using SIGIO and buffering characters itself,
   or using CBREAK mode and making C-g cause SIGINT.
   The choice is controlled by the variable interrupt_input.
   Define INTERRUPT_INPUT to make interrupt_input = 1 the default (use SIGIO)

   SIGIO can be used only on systems that implement it (4.2 and 4.3).
   CBREAK mode has two disadvantages
     1) At least in 4.2, it is impossible to handle the Meta key properly.
        I hear that in system V this problem does not exist.
     2) Control-G causes output to be discarded.
        I do not know whether this can be fixed in system V.

   Another method of doing input is planned but not implemented.
   It would have Emacs fork off a separate process
   to read the input and send it to the true Emacs process
   through a pipe.
*/

/* There have been suggestions made to add SIGIO to Linux.  If this
   is done, you may, at your discretion, uncomment the line below.
*/

/* #define INTERRUPT_INPUT */

/* Letter to use in finding device name of first pty,
  if system supports pty's.  'p' means it is /dev/ptyp0  */

#define FIRST_PTY_LETTER 'p'

/*
 *	Define HAVE_TERMIOS if the system provides POSIX-style
 *	functions and macros for terminal control.
 */

#define HAVE_TERMIOS

/*
 *	Define HAVE_TIMEVAL if the system supports the BSD style clock values.
 *	Look in <sys/time.h> for a timeval structure.
 */

#define HAVE_TIMEVAL

/*
 *	Define HAVE_SELECT if the system supports the `select' system call.
 */

#define HAVE_SELECT

/*
 *	Define HAVE_PTYS if the system supports pty devices.
 */

#define HAVE_PTYS

/* Uncomment this later when other problems are dealt with -mkj */

#define HAVE_SOCKETS

/* Define this symbol if your system has the functions bcopy, etc. */

#define BSTRING

/* subprocesses should be defined if you want to
   have code for asynchronous subprocesses
   (as used in M-x compile and M-x shell).
   This is generally OS dependent, and not supported
   under most USG systems. */

#define subprocesses

/* define MAIL_USE_FLOCK if the mailer uses flock
   to interlock access to /usr/spool/mail/$USER.
   The alternative is that a lock file named
   /usr/spool/mail/$USER.lock.  */

/* Both are used in Linux by different mail programs.  I assume that most
   people are using newer mailers that have heard of flock.  Change this
   if you need to. */

#define MAIL_USE_FLOCK

/* Define CLASH_DETECTION if you want lock files to be written
   so that Emacs can tell instantly when you try to modify
   a file that someone else has modified in his Emacs.  */

#define CLASH_DETECTION

/* Here, on a separate page, add any special hacks needed
   to make Emacs work on this system.  For example,
   you might define certain system call names that don't
   exist on your system, or that do different things on
   your system and must be used only through an encapsulation
   (Which you should place, by convention, in sysdep.c).  */

/* On POSIX systems the system calls are interruptible by signals
 that the user program has elected to catch.  Thus the system call
 must be retried in these cases.  To handle this without massive
 changes in the source code, we remap the standard system call names
 to names for our own functions in sysdep.c that do the system call
 with retries. */

#define read sys_read
#define write sys_write
#define open sys_open
#define close sys_close

#define INTERRUPTIBLE_OPEN
#define INTERRUPTIBLE_CLOSE
#define INTERRUPTIBLE_IO

/* If you mount the proc file system somewhere other than /proc
   you will have to uncomment the following and make the proper
   changes */

/* #define LINUX_LDAV_FILE "/proc/loadavg" */

/* This is needed for disknew.c:update_frame */

#ifdef emacs
#include <stdio.h>  /* Get the definition of _IO_STDIO_H.  */
#ifdef _IO_STDIO_H
/* new C libio names */
#define GNU_LIBRARY_PENDING_OUTPUT_COUNT(FILE) \
  ((FILE)->_IO_write_ptr - (FILE)->_IO_write_base)
#else /* !_IO_STDIO_H */
/* old C++ iostream names */
#define GNU_LIBRARY_PENDING_OUTPUT_COUNT(FILE) \
  ((FILE)->_pptr - (FILE)->_pbase)
#endif /* !_IO_STDIO_H */
#endif /* emacs */

/* Linux has crt0.o in a non-standard place */
#define START_FILES pre-crt0.o /usr/lib/crt0.o

/* As of version 1.1.51, Linux does not actually implement SIGIO.  */
/* Here we assume that signal.h is already included.  */
#ifdef emacs
#undef SIGIO
#endif

/* This is needed for sysdep.c */

#define NO_SIOCTL_H           /* don't have sioctl.h */

#define HAVE_GETPAGESIZE
#define HAVE_VFORK
#define HAVE_SYS_SIGLIST
#define HAVE_GETWD            /* cure conflict with getcwd? */

#define SYSV_SYSTEM_DIR       /* use dirent.h */

#define POSIX                 /* affects getpagesize.h and systty.h */
#define POSIX_SIGNALS

/* libc-linux/sysdeps/linux/i386/ulimit.c says that due to shared library, */
/* we cannot get the maximum address for brk */
#define ULIMIT_BREAK_VALUE (32*1024*1024)

#define SEGMENT_MASK ((SEGMENT_SIZE)-1)

/* Best not to include -lg, unless it is last on the command line */
#define LIBS_DEBUG
#define LIBS_TERMCAP -ltermcap -lcurses /* save some space with shared libs*/
#define LIB_STANDARD -lc /* avoid -lPW */
#ifdef HAVE_X11
#define LD_SWITCH_SYSTEM -L/usr/X386/lib
#endif

/* Don't use -g in test compiles in configure.
   This is so we will use the same shared libs for that linking
   that are used when linking temacs.  */
#ifdef THIS_IS_CONFIGURE
#define C_DEBUG_SWITCH
#endif

/* Let's try this out, just in case.
   Nah.  Rik Faith <faith@cs.unc.edu> says it doesn't work well.  */
/* #define SIGNALS_VIA_CHARACTERS */

/* Rob Malouf <malouf@csli.stanford.edu> says:
   SYSV IPC is standard a standard part of Linux since version 0.99pl10,
   and is a very common addition to previous versions.  */

#ifdef TERM
#define LIBS_MACHINE -lclient
#define C_SWITCH_SYSTEM -D_BSD_SOURCE -I/usr/src/term
#else
/* alane@wozzle.linet.org says that -lipc is not a separate library,
   since libc-4.4.1.  So -lipc was deleted.  */
#define LIBS_MACHINE
#define C_SWITCH_SYSTEM -D_BSD_SOURCE
#endif

#define HAVE_SYSVIPC

#ifdef LINUX_QMAGIC

#define HAVE_TEXT_START
#define UNEXEC unexsunos4.o
#define N_PAGSIZ(x) PAGE_SIZE

#else /* not LINUX_QMAGIC */

#define A_TEXT_OFFSET(hdr) (N_MAGIC(hdr) == QMAGIC ? sizeof (struct exec) : 0)
#define A_TEXT_SEEK(hdr) (N_TXTOFF(hdr) + A_TEXT_OFFSET(hdr))
#define ADJUST_EXEC_HEADER \
  unexec_text_start = N_TXTADDR(ohdr) + A_TEXT_OFFSET(ohdr)

#endif /* not LINUX_QMAGIC */

#if 0
/* In 19.23 and 19.24, configure sometimes fails to define these.
   It has to do with the fact that configure uses CFLAGS when linking
   while Makefile.in.in (erroneously) fails to do so when linking temacs.  */
#ifndef HAVE_GETTIMEOFDAY
#define HAVE_GETTIMEOFDAY
#endif
#ifndef HAVE_MKDIR
#define HAVE_MKDIR
#endif
#ifndef HAVE_RMDIR
#define HAVE_RMDIR
#endif
#ifndef HAVE_XSCREENNUMBEROFSCREEN
#define HAVE_XSCREENNUMBEROFSCREEN
#endif
#ifndef HAVE_XRMSETDATABASE
#define HAVE_XRMSETDATABASE
#endif
#endif /* 0 */
