inform user that ifconfig can correctly show only first 8 bytes of Infiniband hw address

lib/ib.c

@@ -47,7 +47,8 @@ static const char *pr_ib(const char *ptr)
 	pos += sprintf(pos, "%02X:", (*ptr++ & 0377));
     }
     buff[strlen(buff) - 1] = '\0';
-
+    char *ib_warning = "Infiniband hardware address can be incorrect! Please read BUGS section in ifconfig(8).";
+    fprintf(stderr, _(ib_warning));
     /* snprintf(buff, sizeof(buff), "%02X:%02X:%02X:%02X:%02X:%02X",
 	     (ptr[0] & 0377), (ptr[1] & 0377), (ptr[2] & 0377),
 	     (ptr[3] & 0377), (ptr[4] & 0377), (ptr[5] & 0377)

man/en_US/ifconfig.8

@@ -211,6 +211,16 @@ for more information.
 .br
 .I /proc/net/if_inet6
 .SH BUGS
+Ifconfig uses the ioctl access method to get the full address information,
+which limits hardware addresses to 8 bytes.
+Because Infiniband hardware address has 20 bytes,
+only the first 8 bytes are displayed correctly.
+Please use
+.B ip link
+command from
+.B iproute2
+package to display link layer informations including the hardware address.
+.LP
 While appletalk DDP and IPX addresses will be displayed they cannot be
 altered by this command.
 .SH SEE ALSO