It is possible to have no hosts database at all. Pointed out in

Subject: [PATCH: 7131] PWPASSWD problem for passwd less pwd's
Message-ID: <Pine.OSF.4.10.10010031203470.388222-100000@aspara.forte.com>

p4raw-id: //depot/perl@7139

diff --git a/Configure b/Configure
index ae6712f..dadb98a 100755 (executable)
--- a/Configure
+++ b/Configure
@@ -20,7 +20,7 @@
 
 # $Id: Head.U,v 3.0.1.9 1997/02/28 15:02:09 ram Exp $
 #
-# Generated on Tue Oct  3 05:18:15 EET DST 2000 [metaconfig 3.0 PL70]
+# Generated on Wed Oct  4 01:09:27 EET DST 2000 [metaconfig 3.0 PL70]
 # (with additional metaconfig patches by perlbug@perl.org)
 
 cat >/tmp/c1$$ <<EOF
@@ -7116,18 +7116,23 @@ case "$myhostname" in
                                        /[       ]$myhostname[  . ]/p" > hosts
                }
                tmp_re="[       . ]"
-               $test x`$awk "/[0-9].*[  ]$myhostname$tmp_re/ { sum++ }
+               if $test -f hosts; then
+                       $test x`$awk "/[0-9].*[  ]$myhostname$tmp_re/ { sum++ }
                             END { print sum }" hosts` = x1 || tmp_re="[         ]"
-               dflt=.`$awk "/[0-9].*[   ]$myhostname$tmp_re/ {for(i=2; i<=NF;i++) print \\\$i}" \
-                       hosts | $sort | $uniq | \
-                       $sed -n -e "s/$myhostname\.\([-a-zA-Z0-9_.]\)/\1/p"`
-               case `$echo X$dflt` in
-               X*\ *)  echo "(Several hosts in /etc/hosts matched hostname)"
+                       dflt=.`$awk "/[0-9].*[   ]$myhostname$tmp_re/ {for(i=2; i<=NF;i++) print \\\$i}" \
+                               hosts | $sort | $uniq | \
+                               $sed -n -e "s/$myhostname\.\([-a-zA-Z0-9_.]\)/\1/p"`
+                       case `$echo X$dflt` in
+                       X*\ *)  echo "(Several hosts in the database matched hostname)"
+                               dflt=.
+                               ;;
+                       X.) echo "(You do not have fully-qualified names in the hosts database)"
+                               ;;
+                       esac
+               else
+                       echo "(I cannot locate a hosts database anywhere)"
                        dflt=.
-                       ;;
-               X.) echo "(You do not have fully-qualified names in /etc/hosts)"
-                       ;;
-               esac
+               fi
                case "$dflt" in
                .)
                        tans=`./loc resolv.conf X /etc /usr/etc`