Bug 97687

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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030529

Description of problem:
On RedHat 7.3, 8 and 9, adding "ldap" to the "hosts" DB in "/etc/nsswitch.conf"
seems to work _partially_. It's OK for "ping" but not OK for many other apps
like "telnet", "ssh".
Its OK for "python1" but not OK for "python2". I think it comes from the
libc call: "ping" and "python1" use "gethostbyname()", while "telnet" and
"python2" use "getaddrinfo()". An interesting case: "getent hosts" lists
the hosts defined in the LDAP DB, but a match like "getent hosts <hostname>"
returns nothing if <hostname> is defined in LDAP, and does return
an answer if <hostname> is defined in "/etc/hosts".


Version-Release number of selected component (if applicable):
glibc-2.3.2-4.80.6

How reproducible:
Always

Steps to Reproduce:
1. Configure the hostname resolution to use LDAP. (Put a line
   "hosts: files dns ldap" in "/etc/nsswitch.conf")
2. Configure two hosts, one beeing resolved with LDAP, the other
   with the "/etc/hosts" file. (Put a line
   "192.168.100.26 ldap1 bugzilla" in "/etc/hosts". Put a record
   for "rx13" in the "ou=Hosts,dc=???,dc=com" LDAP DB.
3. Try to ping and telnet to "bugzilla" and "rx13":
   |> ping bugzilla
   |> telnet bugzilla
   |> ping rx13
   |> telnet rx13
   Output:
   |> [olheureu@wks13 olheureu]$ ping rx11
   |> PING rx11 (192.168.100.201) from 192.168.100.23 : 56(84) bytes    of data.
   |> 64 bytes from rx11 (192.168.100.201): icmp_seq=1 ttl=255    time=2.56 ms
   |> 64 bytes from rx11 (192.168.100.201): icmp_seq=2 ttl=255 time=1.85 ms
   |> 
   |> --- rx11 ping statistics ---
   |> 2 packets transmitted, 2 received, 0% loss, time 1010ms
   |> rtt min/avg/max/mdev = 1.856/2.212/2.569/0.359 ms
   |> [olheureu@wks13 olheureu]$ telnet rx11
   |> telnet: rx11: Name or service not known
   |> rx11: Unknown host
   |> [olheureu@wks13 olheureu]$



Actual Results:  With "bugzilla", ping and telnet find the host. With "rx13", ping
find the host but telnet doesn't.

Expected Results:  "rx13" beeing found by telnet as it is by ping.

Additional info:

This bug may be correlated with bug 54646.
Because Posix says "gethostbyname()" is obsolete and should be
replaced by "getaddrinfo()", I guess more and more apps will
use "getaddrinfo()" in the future.