Path: csiph.com!eternal-september.org!feeder.eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail
From: Knute Johnson <knute2020@585ranch.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: InetAddress.isReachable() ?
Date: Sun, 1 Nov 2020 10:30:52 -0600
Organization: A noiseless patient Spider
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Xref: csiph.com comp.lang.java.programmer:39648

On 10/29/20 8:47 PM, Arne Vajhøj wrote:
> On 10/29/2020 4:23 PM, Knute Johnson wrote:
>> I'm not sure why Java has the privilege issue with 
>> InetAddress.isReachable() but it does.
> 
> Someone thought that use of ICMP in Linux should
> require privs.
> 
> The ping executable is rws while the java
> executable is rwx.
> 
> Arne
> 
> 

OK, so that got me curious and I checked on my Xubuntu box that I was 
using when writing this program and found this:

/usr/bin$ ls -al ping
-rwxr-xr-x 1 root root 72776 Jan 30  2020 ping

But then for fun I looked on my RaspberryPi and found:

~ $ ls -al /bin/ping
-rwsr-xr-x 1 root root 55720 Jan 13  2020 /bin/ping

The Buntus are usually fairly lax in some of their settings but I 
thought this was interesting.  Useless but interesting.