java 1.5 InetAddr doesn't consult system hosts file unless run from [pseudo]tty?

From:

"trawick@gmail.com" <trawick@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

15 Nov 2006 06:56:55 -0800

Message-ID:

<1163602615.258937.203330@b28g2000cwb.googlegroups.com>

A simple test program can look up hostnames defined in system host file
as long as it is run with a tty. When run without a tty, it can't find
the hostnames. This issue leads to the failure of an application when
run remotely.

Various properties tweaked; seen on AIX and Linux/PPC too with
IBM-supplied java 1.5; recreated below with current Sun java 1.5 for
Solaris; an application which has the same issue with java 1.5 ran for
ages with java 1.4.2 on many platforms with no such issue

Has anybody seen anything similar?

From a Solaris 9 run with freshly downloaded/untweaked jre 1.5:

$ cat /etc/inet/ipnodes
#
# Internet host table
#
#::1 localhost
::1 ipv6host
127.0.0.1 ipv4host

$ cat useinetaddr.sh
#!/bin/sh

PATH=$HOME/jre1.5.0_09/bin:$PATH
export PATH

java -version

java UseInetAddr ipv4host
java UseInetAddr ipv6host

$ cat UseInetAddr.java
import java.net.InetAddress;

public class UseInetAddr {

    public static void main(String[] args) throws Exception {
        InetAddress inetAddr;

        System.out.println("looking up " + args[0] + "...");
        inetAddr = InetAddress.getByName(args[0]);
        System.out.println("okay");
    }
}

Run it directly from remote terminal... no problems

$ ./useinetaddr.sh
java version "1.5.0_09"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_09-b03)
Java HotSpot(TM) Client VM (build 1.5.0_09-b03, mixed mode, sharing)
looking up ipv4host...
okay
looking up ipv6host...
okay

Run it via ssh to self... fails to find the definition

$ ssh 127.0.0.1 ./useinetaddr.sh
java version "1.5.0_09"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_09-b03)
Java HotSpot(TM) Client VM (build 1.5.0_09-b03, mixed mode, sharing)
looking up ipv4host...
Exception in thread "main" java.net.UnknownHostException: ipv4host:
ipv4host
        at java.net.InetAddress.getAllByName0(Unknown Source)
        at java.net.InetAddress.getAllByName0(Unknown Source)
        at java.net.InetAddress.getAllByName(Unknown Source)
        at java.net.InetAddress.getByName(Unknown Source)
        at UseInetAddr.main(UseInetAddr.java:9)
looking up ipv6host...
Exception in thread "main" java.net.UnknownHostException: ipv6host:
ipv6host
        at java.net.InetAddress.getAllByName0(Unknown Source)
        at java.net.InetAddress.getAllByName0(Unknown Source)
        at java.net.InetAddress.getAllByName(Unknown Source)
        at java.net.InetAddress.getByName(Unknown Source)
        at UseInetAddr.main(UseInetAddr.java:9)

Run it via ssh to self, but tell ssh to allocate a pseudoterminal using
ssh -t option... works...

$ ssh -t 127.0.0.1 ./useinetaddr.sh
java version "1.5.0_09"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_09-b03)
Java HotSpot(TM) Client VM (build 1.5.0_09-b03, mixed mode, sharing)
looking up ipv4host...
okay
looking up ipv6host...
okay
Connection to 127.0.0.1 closed.

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