diff --git a/chmod_chown_chgrp.c b/chmod_chown_chgrp.c
index 4fc986904..9714e1ca5 100644
--- a/chmod_chown_chgrp.c
+++ b/chmod_chown_chgrp.c
@@ -49,6 +49,7 @@ static int fileAction(const char *fileName, struct stat *statbuf, void* junk)
 	switch (whichApp) {
 	case CHGRP_APP:
 	case CHOWN_APP:
+	/* Don't use lchown for libc5 or glibc older then 2.1.x */
 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 		if (lchown
 			(fileName, (whichApp == CHOWN_APP) ? uid : statbuf->st_uid,
diff --git a/dutmp.c b/dutmp.c
index a75a6e392..26253b445 100644
--- a/dutmp.c
+++ b/dutmp.c
@@ -41,11 +41,9 @@ extern int dutmp_main(int argc, char **argv)
 		}
 	}
 
-/* Kludge around the fact that the binary format for utmp has changed, and the
- * fact the stupid libc doesn't have a reliable #define to announce that libc5
- * is being used.  sigh.
- */
-#if ! defined __GLIBC__ || defined __UCLIBC__
+/* Kludge around the fact that the binary format for utmp has changed. */
+#if __GNU_LIBRARY__ < 5
+	/* Linux libc5 */
 	while (read(file, (void*)&ut, sizeof(struct utmp))) {
 		printf("%d|%d|%s|%s|%s|%s|%s|%lx\n",
 				ut.ut_type, ut.ut_pid, ut.ut_line,
@@ -54,6 +52,7 @@ extern int dutmp_main(int argc, char **argv)
 				(long)ut.ut_addr);
 	}
 #else
+	/* Glibc, uClibc, etc */
 	while (read(file, (void*)&ut, sizeof(struct utmp))) {
 		printf("%d|%d|%s|%s|%s|%s|%d|%d|%ld|%ld|%ld|%x\n",
 		ut.ut_type, ut.ut_pid, ut.ut_line,
diff --git a/include/libbb.h b/include/libbb.h
index 0001cac6f..6133b19d3 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -34,9 +34,8 @@
 #endif
 
 #include <features.h>
-/* Stupid libc doesn't have a reliable way for use to know 
- * that libc5 is being used.   Assume this is good enough */ 
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+
+#if __GNU_LIBRARY__ < 5
 /* libc5 doesn't define socklen_t */
 typedef unsigned int socklen_t;
 /* libc5 doesn't implement BSD 4.4 daemon() */
diff --git a/init.c b/init.c
index bf992b52c..619421891 100644
--- a/init.c
+++ b/init.c
@@ -85,13 +85,13 @@ static const int RB_ENABLE_CAD = 0x89abcdef;
 static const int RB_DISABLE_CAD = 0;
 #define RB_POWER_OFF    0x4321fedc
 static const int RB_AUTOBOOT = 0x01234567;
-#if defined(__GLIBC__) || defined (__UCLIBC__)
-#include <sys/reboot.h>
+
+#if __GNU_LIBRARY__ > 5
+  #include <sys/reboot.h>
   #define init_reboot(magic) reboot(magic)
 #else
   #define init_reboot(magic) reboot(0xfee1dead, 672274793, magic)
 #endif
-#endif
 
 #ifndef _PATH_STDPATH
 #define _PATH_STDPATH	"/usr/bin:/bin:/usr/sbin:/sbin"
@@ -112,11 +112,11 @@ static const int RB_AUTOBOOT = 0x01234567;
 
 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
 
-#if defined(__GLIBC__)
-#include <sys/kdaemon.h>
+#if __GNU_LIBRARY__ > 5
+	#include <sys/kdaemon.h>
 #else
-extern int bdflush (int func, long int data);
-#endif							/* __GLIBC__ */
+	extern int bdflush (int func, long int data);
+#endif
 
 
 #define VT_PRIMARY   "/dev/tty1"     /* Primary virtual console */
diff --git a/init/init.c b/init/init.c
index bf992b52c..619421891 100644
--- a/init/init.c
+++ b/init/init.c
@@ -85,13 +85,13 @@ static const int RB_ENABLE_CAD = 0x89abcdef;
 static const int RB_DISABLE_CAD = 0;
 #define RB_POWER_OFF    0x4321fedc
 static const int RB_AUTOBOOT = 0x01234567;
-#if defined(__GLIBC__) || defined (__UCLIBC__)
-#include <sys/reboot.h>
+
+#if __GNU_LIBRARY__ > 5
+  #include <sys/reboot.h>
   #define init_reboot(magic) reboot(magic)
 #else
   #define init_reboot(magic) reboot(0xfee1dead, 672274793, magic)
 #endif
-#endif
 
 #ifndef _PATH_STDPATH
 #define _PATH_STDPATH	"/usr/bin:/bin:/usr/sbin:/sbin"
@@ -112,11 +112,11 @@ static const int RB_AUTOBOOT = 0x01234567;
 
 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
 
-#if defined(__GLIBC__)
-#include <sys/kdaemon.h>
+#if __GNU_LIBRARY__ > 5
+	#include <sys/kdaemon.h>
 #else
-extern int bdflush (int func, long int data);
-#endif							/* __GLIBC__ */
+	extern int bdflush (int func, long int data);
+#endif
 
 
 #define VT_PRIMARY   "/dev/tty1"     /* Primary virtual console */
diff --git a/interface.c b/interface.c
index a80cd5524..a043d7223 100644
--- a/interface.c
+++ b/interface.c
@@ -3,7 +3,7 @@
  *              that either displays or sets the characteristics of
  *              one or more of the system's networking interfaces.
  *
- * Version:     $Id: interface.c,v 1.5 2001/03/15 15:37:48 mjn3 Exp $
+ * Version:     $Id: interface.c,v 1.6 2001/04/09 23:52:18 andersen Exp $
  *
  * Author:      Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  *              and others.  Copyright 1993 MicroWalt Corporation
@@ -115,7 +115,7 @@ struct in6_ifreq {
 #endif				/* HAVE_AFINET6 */
 
 #if HAVE_AFIPX
-#if (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1)
+#if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 #include <netipx/ipx.h>
 #else
 #include "ipx.h"
diff --git a/libbb/daemon.c b/libbb/daemon.c
index 55a776ce0..6d4169ed5 100644
--- a/libbb/daemon.c
+++ b/libbb/daemon.c
@@ -32,9 +32,7 @@
 #include <unistd.h>
 
 
-/* Stupid libc doesn't have a reliable way for use to know 
- * that libc5 is being used.   Assume this is good enough */ 
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+#if __GNU_LIBRARY__ < 5
 
 int daemon( int nochdir, int noclose )
 {
diff --git a/libbb/libbb.h b/libbb/libbb.h
index 0001cac6f..6133b19d3 100644
--- a/libbb/libbb.h
+++ b/libbb/libbb.h
@@ -34,9 +34,8 @@
 #endif
 
 #include <features.h>
-/* Stupid libc doesn't have a reliable way for use to know 
- * that libc5 is being used.   Assume this is good enough */ 
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+
+#if __GNU_LIBRARY__ < 5
 /* libc5 doesn't define socklen_t */
 typedef unsigned int socklen_t;
 /* libc5 doesn't implement BSD 4.4 daemon() */
diff --git a/logread.c b/logread.c
index 19e8aefa6..d3349625c 100644
--- a/logread.c
+++ b/logread.c
@@ -35,9 +35,7 @@
 #include <setjmp.h>
 #include "busybox.h"
 
-/* Stupid libc doesn't have a reliable way for use to know 
- * that libc5 is being used.   Assume this is good enough */ 
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+#if __GNU_LIBRARY__ < 5
 #error Sorry.  Looks like you are using libc5.  
 #error libc5 shm support isnt good enough.
 #error Please disable BB_FEATURE_IPC_SYSLOG 
diff --git a/miscutils/dutmp.c b/miscutils/dutmp.c
index a75a6e392..26253b445 100644
--- a/miscutils/dutmp.c
+++ b/miscutils/dutmp.c
@@ -41,11 +41,9 @@ extern int dutmp_main(int argc, char **argv)
 		}
 	}
 
-/* Kludge around the fact that the binary format for utmp has changed, and the
- * fact the stupid libc doesn't have a reliable #define to announce that libc5
- * is being used.  sigh.
- */
-#if ! defined __GLIBC__ || defined __UCLIBC__
+/* Kludge around the fact that the binary format for utmp has changed. */
+#if __GNU_LIBRARY__ < 5
+	/* Linux libc5 */
 	while (read(file, (void*)&ut, sizeof(struct utmp))) {
 		printf("%d|%d|%s|%s|%s|%s|%s|%lx\n",
 				ut.ut_type, ut.ut_pid, ut.ut_line,
@@ -54,6 +52,7 @@ extern int dutmp_main(int argc, char **argv)
 				(long)ut.ut_addr);
 	}
 #else
+	/* Glibc, uClibc, etc */
 	while (read(file, (void*)&ut, sizeof(struct utmp))) {
 		printf("%d|%d|%s|%s|%s|%s|%d|%d|%ld|%ld|%ld|%x\n",
 		ut.ut_type, ut.ut_pid, ut.ut_line,
diff --git a/miscutils/update.c b/miscutils/update.c
index ce2b6cf08..a6550b05c 100644
--- a/miscutils/update.c
+++ b/miscutils/update.c
@@ -33,11 +33,11 @@
 #include <unistd.h> /* for getopt() */
 #include <stdlib.h>
 
-#if defined(__GLIBC__)
-#include <sys/kdaemon.h>
+#if __GNU_LIBRARY__ > 5
+	#include <sys/kdaemon.h>
 #else
-extern int bdflush (int func, long int data);
-#endif							/* __GLIBC__ */
+	extern int bdflush (int func, long int data);
+#endif
 
 #include "busybox.h"
 
diff --git a/networking/ping.c b/networking/ping.c
index 8ac963076..8b82dcaac 100644
--- a/networking/ping.c
+++ b/networking/ping.c
@@ -1,6 +1,6 @@
 /* vi: set sw=4 ts=4: */
 /*
- * $Id: ping.c,v 1.39 2001/03/14 01:23:07 andersen Exp $
+ * $Id: ping.c,v 1.40 2001/04/09 23:52:18 andersen Exp $
  * Mini ping implementation for busybox
  *
  * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
@@ -54,7 +54,7 @@
 
 /* It turns out that libc5 doesn't have proper icmp support
  * built into it header files, so we have to supplement it */
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+#if __GNU_LIBRARY__ < 5
 static const int ICMP_MINLEN = 8;				/* abs minimum */
 
 struct icmp_ra_addr
diff --git a/ping.c b/ping.c
index 8ac963076..8b82dcaac 100644
--- a/ping.c
+++ b/ping.c
@@ -1,6 +1,6 @@
 /* vi: set sw=4 ts=4: */
 /*
- * $Id: ping.c,v 1.39 2001/03/14 01:23:07 andersen Exp $
+ * $Id: ping.c,v 1.40 2001/04/09 23:52:18 andersen Exp $
  * Mini ping implementation for busybox
  *
  * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
@@ -54,7 +54,7 @@
 
 /* It turns out that libc5 doesn't have proper icmp support
  * built into it header files, so we have to supplement it */
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+#if __GNU_LIBRARY__ < 5
 static const int ICMP_MINLEN = 8;				/* abs minimum */
 
 struct icmp_ra_addr
diff --git a/sysklogd/logread.c b/sysklogd/logread.c
index 19e8aefa6..d3349625c 100644
--- a/sysklogd/logread.c
+++ b/sysklogd/logread.c
@@ -35,9 +35,7 @@
 #include <setjmp.h>
 #include "busybox.h"
 
-/* Stupid libc doesn't have a reliable way for use to know 
- * that libc5 is being used.   Assume this is good enough */ 
-#if ! defined __GLIBC__ && ! defined __UCLIBC__
+#if __GNU_LIBRARY__ < 5
 #error Sorry.  Looks like you are using libc5.  
 #error libc5 shm support isnt good enough.
 #error Please disable BB_FEATURE_IPC_SYSLOG 
diff --git a/update.c b/update.c
index ce2b6cf08..a6550b05c 100644
--- a/update.c
+++ b/update.c
@@ -33,11 +33,11 @@
 #include <unistd.h> /* for getopt() */
 #include <stdlib.h>
 
-#if defined(__GLIBC__)
-#include <sys/kdaemon.h>
+#if __GNU_LIBRARY__ > 5
+	#include <sys/kdaemon.h>
 #else
-extern int bdflush (int func, long int data);
-#endif							/* __GLIBC__ */
+	extern int bdflush (int func, long int data);
+#endif
 
 #include "busybox.h"