Update.

1999-05-26  Ulrich Drepper  <drepper@cygnus.com>

	* config.h.in: Add __LINUX_KERNEL_VERSION.
	* configure.in: Recognize --enable-kernel.
	* sysdeps/unix/sysv/linux/configure.in: Check for correct kernel
	headers if --enable-kernel is given and set __LINUX_KERNEL_VERSION
	appropriately.
	* sysdeps/unix/sysv/linux/init-first.c: If minimal kernel version is
	given perform runtime test.

	* sysdeps/unix/sysv/linux/kernel-features.h: New file.
	* sysdeps/unix/sysv/linux/getcwd.c: Elide compatibility code if
	minimal supported kernel is known to have the feature.
	* sysdeps/unix/sysv/linux/poll.c: Likewise.
	* sysdeps/unix/sysv/linux/pread.c: Likewise.
	* sysdeps/unix/sysv/linux/pread64.c: Likewise.
	* sysdeps/unix/sysv/linux/pwrite.c: Likewise.
	* sysdeps/unix/sysv/linux/pwrite64.c: Likewise.
	* sysdeps/unix/sysv/linux/seteuid.c: Likewise.
	* sysdeps/unix/sysv/linux/sigaction.c: Likewise.
	* sysdeps/unix/sysv/linux/sigprocmask.c: Likewise.
	* sysdeps/unix/sysv/linux/sigsuspend.c: Likewise.
	* sysdeps/unix/sysv/linux/testrtsig.h: Likewise.
	* sysdeps/unix/sysv/linux/i386/chown.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/pread.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/pread64.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/pwrite.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/pwrite64.c: Likewise.

	* sysdeps/unix/sysv/linux/sysctl.c: Add __sysctl alias.

1 files changed, 74 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
new file mode 100644
index 0000000000..6813853ccc
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/kernel-features.h
@@ -0,0 +1,74 @@
+/* Set flags signalling availability of kernel features based on given
+   kernel version number.
+   Copyright (C) 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* This file must not contain any C code.  At least it must be protected
+   to allow using the file also in assembler files.  */
+
+/* XXX For testing.  */
+#define __LINUX_KERNEL_VERSION 131584
+
+#ifndef __LINUX_KERNEL_VERSION
+/* We assume the worst; all kernels should be supported.  */
+# define __LINUX_KERNEL_VERSION	0
+#endif
+
+/* We assume for __LINUX_KERNEL_VERSION the same encoding used in
+   linux/version.h.  I.e., the major, minor, and subminor all get a
+   byte with the major number being in the highest byte.  This means
+   we can do numeric comparisons.
+
+   In the following we will define certain symbols depending on
+   whether the describes kernel feature is available in the kernel
+   version given by __LINUX_KERNEL_VERSION.  We are not always exactly
+   recording the correct versions in which the features were
+   introduced.  If somebody cares these values can afterwards be
+   corrected.  Most of the numbers here are set corresponding to
+   2.2.0.  */
+
+/* `getcwd' system call.  */
+#if __LINUX_KERNEL_VERSION >= 131584
+# define __ASSUME_GETCWD_SYSCALL	1
+#endif
+
+/* Real-time signal became usable in 2.1.70.  */
+#if __LINUX_KERNEL_VERSION >= 131398
+# define __ASSUME_REALTIME_SIGNALS	1
+#endif
+
+/* When were the `pread'/`pwrite' syscalls introduced?  */
+#if __LINUX_KERNEL_VERSION >= 131584
+# define __ASSUME_PREAD_SYSCALL		1
+# define __ASSUME_PWRITE_SYSCALL	1
+#endif
+
+/* When was `poll' introduced?  */
+#if __LINUX_KERNEL_VERSION >= 131584
+# define __ASSUME_POLL_SYSCALL		1
+#endif
+
+/* The `lchown' syscall was introduced in 2.1.80.  */
+#if __LINUX_KERNEL_VERSION >= 131408
+# define __ASSUME_LCHOWN_SYSCALL	1
+#endif
+
+/* When did the `setresuid' sysall became available?  */
+#if __LINUX_KERNEL_VERSION >= 131584
+# define __ASSUME_SETRESUID_SYSCALL	1
+#endif