A question about gethostbyname()

zhoujun · August 31, 2000, 6:19am

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t find
it out and correct it.

Thank you for any info.

Zhoujun

Mario_Charest1 · August 31, 2000, 6:19am

What is your netmap, from what I understand it should be 255.255.255.0

“zhoujun” <jzhou@mail.nairc.ac.cn> wrote in message
news:8ol2a1$t7r$1@inn.qnx.com…

Thank you !
After restarting my computer, I tried to ping some involved IP addresses,I
found I can ping to any IP addresses in my subnet. And I can ping to my
nameserver and web servers in Internet,too.

My host: ..75.96
My nameserver: ..75.90
My gateway: ..75.8

But,I could not ping to ..120.20 although system knows the gateway
..75.8.
After adding the subnet by command “route add -net ..120 ..75.8”, I
can ping to ..120.20. I also want to know this cause.

The problem about gethostbyname() still exists.

Mitchell Schoenbrun <> maschoen@pobox.com> > wrote in message
news:> Voyager.000830233118.4698A@schoenbrun.com> …
Previously, zhoujun wrote in comp.os.qnx:

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t
find
it out and correct it.

Well the most likely thing that comes to mind is that the IP’s
in your /etc/resolv.conf point to name servers that are not
working. You might want to try pinging them for starters.

Mitchell Schoenbrun --------- > maschoen@pobox.com

\

Mitchell_Schoenbrun · August 31, 2000, 6:31am

Previously, zhoujun wrote in comp.os.qnx:

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t find
it out and correct it.

Well the most likely thing that comes to mind is that the IP’s
in your /etc/resolv.conf point to name servers that are not
working. You might want to try pinging them for starters.

Mitchell Schoenbrun --------- maschoen@pobox.com

zhoujun · August 31, 2000, 7:42am

Thank you !
After restarting my computer, I tried to ping some involved IP addresses,I
found I can ping to any IP addresses in my subnet. And I can ping to my
nameserver and web servers in Internet,too.

My host: ..75.96
My nameserver: ..75.90
My gateway: ..75.8

But,I could not ping to ..120.20 although system knows the gateway
..75.8.
After adding the subnet by command “route add -net ..120 ..75.8”, I
can ping to ..120.20. I also want to know this cause.

The problem about gethostbyname() still exists.

Mitchell Schoenbrun <maschoen@pobox.com> wrote in message
news:Voyager.000830233118.4698A@schoenbrun.com…

Previously, zhoujun wrote in comp.os.qnx:

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t
find
it out and correct it.

Well the most likely thing that comes to mind is that the IP’s
in your /etc/resolv.conf point to name servers that are not
working. You might want to try pinging them for starters.

Mitchell Schoenbrun --------- > maschoen@pobox.com

Heather_Johnstone · August 31, 2000, 1:24pm

I think Mario means ‘What is your netmask’

I believe you want the netmask to be 255.255.0.0

Heather

Mario Charest <mcharest@zinformatic.com> wrote:

What is your netmap, from what I understand it should be 255.255.255.0

“zhoujun” <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8ol2a1$t7r$> 1@inn.qnx.com> …
Thank you !
After restarting my computer, I tried to ping some involved IP addresses,I
found I can ping to any IP addresses in my subnet. And I can ping to my
nameserver and web servers in Internet,too.

My host: ..75.96
My nameserver: ..75.90
My gateway: ..75.8

But,I could not ping to ..120.20 although system knows the gateway
..75.8.
After adding the subnet by command “route add -net ..120 ..75.8”, I
can ping to ..120.20. I also want to know this cause.

The problem about gethostbyname() still exists.

Mitchell Schoenbrun <> maschoen@pobox.com> > wrote in message
news:> Voyager.000830233118.4698A@schoenbrun.com> …
Previously, zhoujun wrote in comp.os.qnx:

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t
find
it out and correct it.

Well the most likely thing that comes to mind is that the IP’s
in your /etc/resolv.conf point to name servers that are not
working. You might want to try pinging them for starters.

Mitchell Schoenbrun --------- > maschoen@pobox.com

\

Ivan_Bannon1 · August 31, 2000, 9:54pm

Check out the file “/etc/resolv.conf” and be sure it defines your nameserver
correctly. That may be your problem

Ivan

zhoujun <jzhou@mail.nairc.ac.cn> wrote in message
news:8okteh$pvd$1@inn.qnx.com…

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

Ivan_Bannon1 · August 31, 2000, 9:56pm

What??? A netmap of 255.255.255.0? L:ooks like a netmask to me? :}

Mario Charest <mcharest@zinformatic.com> wrote in message
news:8oli4j$7q7$1@inn.qnx.com…

What is your netmap, from what I understand it should be 255.255.255.0

“zhoujun” <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8ol2a1$t7r$> 1@inn.qnx.com> …
Thank you !
After restarting my computer, I tried to ping some involved IP
addresses,I
found I can ping to any IP addresses in my subnet. And I can ping to my
nameserver and web servers in Internet,too.

My host: ..75.96
My nameserver: ..75.90
My gateway: ..75.8

But,I could not ping to ..120.20 although system knows the gateway
..75.8.
After adding the subnet by command “route add -net ..120 ..75.8”,
I
can ping to ..120.20. I also want to know this cause.

The problem about gethostbyname() still exists.

Mitchell Schoenbrun <> maschoen@pobox.com> > wrote in message
news:> Voyager.000830233118.4698A@schoenbrun.com> …
Previously, zhoujun wrote in comp.os.qnx:

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I
can’t
find
it out and correct it.

Well the most likely thing that comes to mind is that the IP’s
in your /etc/resolv.conf point to name servers that are not
working. You might want to try pinging them for starters.

Mitchell Schoenbrun --------- > maschoen@pobox.com

\

Ivan_Bannon1 · August 31, 2000, 9:58pm

The TCP/IP release for 4.25 has a problem in that the ifconfigalways sets
the
netmask to 255.255.255.0 whanever you define the “en1” IP. I have tried to
get to to create a 255.255.0.0, but if you check it always shows ffffff00 as
the
netmask, which is 255.255.255.0

Heather Johnstone <heather@qnx.com> wrote in message
news:8olmaf$4t4$1@nntp.qnx.com…

I think Mario means ‘What is your netmask’ >

I believe you want the netmask to be 255.255.0.0

Heather

Mario Charest <> mcharest@zinformatic.com> > wrote:

What is your netmap, from what I understand it should be 255.255.255.0

“zhoujun” <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8ol2a1$t7r$> 1@inn.qnx.com> …
Thank you !
After restarting my computer, I tried to ping some involved IP
addresses,I
found I can ping to any IP addresses in my subnet. And I can ping to my
nameserver and web servers in Internet,too.

My host: ..75.96
My nameserver: ..75.90
My gateway: ..75.8

But,I could not ping to ..120.20 although system knows the gateway
..75.8.
After adding the subnet by command “route add -net ..120 ..75.8”,
I
can ping to ..120.20. I also want to know this cause.

The problem about gethostbyname() still exists.

Mitchell Schoenbrun <> maschoen@pobox.com> > wrote in message
news:> Voyager.000830233118.4698A@schoenbrun.com> …
Previously, zhoujun wrote in comp.os.qnx:

On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I
can’t
find
it out and correct it.

Well the most likely thing that comes to mind is that the IP’s
in your /etc/resolv.conf point to name servers that are not
working. You might want to try pinging them for starters.

Mitchell Schoenbrun --------- > maschoen@pobox.com

\

zhoujun · September 1, 2000, 2:09am

Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the netmask is
set to 255.255.0.0 or to 255.255.255.0.

Ivan Bannon <ivan.bannon@rjginc.com> wrote in message
news:8omk1t$obg$1@inn.qnx.com…

Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

\

Xiaodan_Tang1 · September 1, 2000, 4:47am

zhoujun <jzhou@mail.nairc.ac.cn> wrote:

Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the netmask is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?
is “nslookup” contact the nameserver ? Is it showing you the right
server address (..75.90)
What is "ping " returned ? Is it resolved the name?
The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?
you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

-xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

\

zhoujun · September 1, 2000, 7:42am

Thank you !
Because ..75.90 is my temp nameserver,so I change my nameserver to
..120.20; then I try to do some test. The following is the result:

“netstat -ni” & “netstat -nr” can work well.

I can ping to ..120.20.
“nslookup” can contact the nameserver, and show the right IP address:
..120.20.
For example,“ping www.qnx.com” returns the right IP address.

4)The name I give “gethostbyname()”, for example, “node1”, is in
“/etc/hosts”,but not in my nameserver. I can’t “nslookup node1” to resolve
it.

But I can get right response with “ping node1” or “telnet node1”.
In the help documents on QNX, I find the following:
The nslookup utility won’t look at /etc/hosts even if the lookup keyword
is used in /etc/resolv.conf.

I add “lookup file bind” to “/etc/resolv.conf” according to your
advice,but, “nslookup node1” still can’t find “node1”.

What’s the matter?

Xiaodan Tang <xtang@qnx.com> wrote in message
news:8onccd$4da$1@nntp.qnx.com…

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the netmask
is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?

is “nslookup” contact the nameserver ? Is it showing you the right
server address (..75.90)

What is "ping " returned ? Is it resolved the name?

The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?

you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

→ xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I
can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

Xiaodan_Tang1 · September 1, 2000, 1:35pm

zhoujun <jzhou@mail.nairc.ac.cn> wrote:

Thank you !
Because ..75.90 is my temp nameserver,so I change my nameserver to
..120.20; then I try to do some test. The following is the result:

“netstat -ni” & “netstat -nr” can work well.

I can ping to ..120.20.

“nslookup” can contact the nameserver, and show the right IP address:
..120.20.

For example,"ping > www.qnx.com> " returns the right IP address.

4)The name I give “gethostbyname()”, for example, “node1”, is in
“/etc/hosts”,but not in my nameserver. I can’t “nslookup node1” to resolve
it.

But I can get right response with “ping node1” or “telnet node1”.
In the help documents on QNX, I find the following:
The nslookup utility won’t look at /etc/hosts even if the lookup keyword
is used in /etc/resolv.conf.

I add “lookup file bind” to “/etc/resolv.conf” according to your
advice,but, “nslookup node1” still can’t find “node1”.

But your “gethostbyname(“node1”)” is succeesed, right? (Cause you could
ping/telnet to “node1”).

nslookup using different resolver as others. It ONLY talk to a nameserver,
resolving names. Others, ping/telnet, they using the resolver in libsocket,
which understand “lookup file bind”, menas they will check /etc/hosts first,
then DNS.

-xtang@qnx.com

What’s the matter?

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8onccd$4da$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the netmask
is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?

is “nslookup” contact the nameserver ? Is it showing you the right
server address (..75.90)

What is "ping " returned ? Is it resolved the name?

The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?

you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

→ xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I
can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

zhoujun · September 2, 2000, 1:24am

It is just the question. My “gethostbyname(“node1”)” is not succeeded On
QNX 4.25, and it returns NULL. It can be rightly executed on my Redhat 6.0.
I am really muddled.

Xiaodan Tang <xtang@qnx.com> wrote in message
news:8oobav$lul$1@nntp.qnx.com…

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
Because ..75.90 is my temp nameserver,so I change my nameserver to
..120.20; then I try to do some test. The following is the result:

“netstat -ni” & “netstat -nr” can work well.

I can ping to ..120.20.

“nslookup” can contact the nameserver, and show the right IP address:
..120.20.

For example,"ping > www.qnx.com> " returns the right IP address.

4)The name I give “gethostbyname()”, for example, “node1”, is in
“/etc/hosts”,but not in my nameserver. I can’t “nslookup node1” to
resolve
it.

But I can get right response with “ping node1” or “telnet node1”.
In the help documents on QNX, I find the following:
The nslookup utility won’t look at /etc/hosts even if the lookup
keyword
is used in /etc/resolv.conf.

I add “lookup file bind” to “/etc/resolv.conf” according to your
advice,but, “nslookup node1” still can’t find “node1”.

But your “gethostbyname(“node1”)” is succeesed, right? (Cause you could
ping/telnet to “node1”).

nslookup using different resolver as others. It ONLY talk to a
nameserver,
resolving names. Others, ping/telnet, they using the resolver in
libsocket,
which understand “lookup file bind”, menas they will check /etc/hosts
first,
then DNS.

→ xtang@qnx.com

What’s the matter?

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8onccd$4da$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the
netmask
is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?

is “nslookup” contact the nameserver ? Is it showing you the right
server address (..75.90)

What is "ping " returned ? Is it resolved the name?

The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?

you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

→ xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I
can’t
find
it out and correct it.

Thank you for any info.

Zhoujun
\

Xiaodan_Tang1 · September 2, 2000, 7:24pm

zhoujun <jzhou@mail.nairc.ac.cn> wrote:

It is just the question. My “gethostbyname(“node1”)” is not succeeded On
QNX 4.25, and it returns NULL. It can be rightly executed on my Redhat 6.0.
I am really muddled.

I was confused.

Are you saying your “gethostbyname(“node1”)” is not succeeded even if
you could “ping node1” from the same QNX 4.25 machine? (ping IS
using gethostbyname() if you give it a name).

xtang@qnx.com

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8oobav$lul$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
Because ..75.90 is my temp nameserver,so I change my nameserver to
..120.20; then I try to do some test. The following is the result:

“netstat -ni” & “netstat -nr” can work well.

I can ping to ..120.20.

“nslookup” can contact the nameserver, and show the right IP address:
..120.20.

For example,"ping > www.qnx.com> " returns the right IP address.

4)The name I give “gethostbyname()”, for example, “node1”, is in
“/etc/hosts”,but not in my nameserver. I can’t “nslookup node1” to
resolve
it.

But I can get right response with “ping node1” or “telnet node1”.
In the help documents on QNX, I find the following:
The nslookup utility won’t look at /etc/hosts even if the lookup
keyword
is used in /etc/resolv.conf.

I add “lookup file bind” to “/etc/resolv.conf” according to your
advice,but, “nslookup node1” still can’t find “node1”.

But your “gethostbyname(“node1”)” is succeesed, right? (Cause you could
ping/telnet to “node1”).

nslookup using different resolver as others. It ONLY talk to a
nameserver,
resolving names. Others, ping/telnet, they using the resolver in
libsocket,
which understand “lookup file bind”, menas they will check /etc/hosts
first,
then DNS.

→ xtang@qnx.com

What’s the matter?

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8onccd$4da$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the
netmask
is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?

is “nslookup” contact the nameserver ? Is it showing you the right
server address (..75.90)

What is "ping " returned ? Is it resolved the name?

The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?

you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

→ xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but, I
can’t
find
it out and correct it.

Thank you for any info.

Zhoujun
\

zhoujun · September 3, 2000, 1:39am

Yes, my question is just that. I have tested the function for many times on
QNX 4.25, but I have never gotten the right result. It always returns
“NULL”;but on the same QNX 4.25 machine, “ping node1” or “telnet node1” can
execute successfully.

Xiaodan Tang <xtang@qnx.com> wrote in message
news:8ork56$jjc$1@nntp.qnx.com…

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
It is just the question. My “gethostbyname(“node1”)” is not succeeded
On
QNX 4.25, and it returns NULL. It can be rightly executed on my Redhat
6.0.
I am really muddled.

I was confused.

Are you saying your “gethostbyname(“node1”)” is not succeeded even if
you could “ping node1” from the same QNX 4.25 machine? (ping IS
using gethostbyname() if you give it a name).

xtang@qnx.com

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8oobav$lul$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
Because ..75.90 is my temp nameserver,so I change my nameserver to
..120.20; then I try to do some test. The following is the result:

“netstat -ni” & “netstat -nr” can work well.

I can ping to ..120.20.

“nslookup” can contact the nameserver, and show the right IP
address:
..120.20.

For example,"ping > www.qnx.com> " returns the right IP address.

4)The name I give “gethostbyname()”, for example, “node1”, is in
“/etc/hosts”,but not in my nameserver. I can’t “nslookup node1” to
resolve
it.

But I can get right response with “ping node1” or “telnet node1”.
In the help documents on QNX, I find the following:
The nslookup utility won’t look at /etc/hosts even if the lookup
keyword
is used in /etc/resolv.conf.

I add “lookup file bind” to “/etc/resolv.conf” according to your
advice,but, “nslookup node1” still can’t find “node1”.

But your “gethostbyname(“node1”)” is succeesed, right? (Cause you could
ping/telnet to “node1”).

nslookup using different resolver as others. It ONLY talk to a
nameserver,
resolving names. Others, ping/telnet, they using the resolver in
libsocket,
which understand “lookup file bind”, menas they will check /etc/hosts
first,
then DNS.

→ xtang@qnx.com

What’s the matter?

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8onccd$4da$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the
netmask
is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?

is “nslookup” contact the nameserver ? Is it showing you the
right
server address (..75.90)

What is "ping " returned ? Is it resolved the name?

The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?

you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

→ xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but,
I
can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

\

Xiaodan_Tang1 · September 3, 2000, 4:06am

zhoujun <jzhou@mail.nairc.ac.cn> wrote:

Yes, my question is just that. I have tested the function for many times on
QNX 4.25, but I have never gotten the right result. It always returns
“NULL”;but on the same QNX 4.25 machine, “ping node1” or “telnet node1” can
execute successfully.

That’s strange. As I said, “ping” IS using a gethostbyname() on
the node name you give it.

Can you do this:

env

ping -c1 node1

cat .c

cc -o mytest .c -lsocket

./mytest

Post the output of each command. The “your test program”.c is
the program showing how your “gethostbyname()” failed.

-xiaodan

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8ork56$jjc$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
It is just the question. My “gethostbyname(“node1”)” is not succeeded
On
QNX 4.25, and it returns NULL. It can be rightly executed on my Redhat
6.0.
I am really muddled.

I was confused.

Are you saying your “gethostbyname(“node1”)” is not succeeded even if
you could “ping node1” from the same QNX 4.25 machine? (ping IS
using gethostbyname() if you give it a name).

xtang@qnx.com

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8oobav$lul$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
Because ..75.90 is my temp nameserver,so I change my nameserver to
..120.20; then I try to do some test. The following is the result:

“netstat -ni” & “netstat -nr” can work well.

I can ping to ..120.20.

“nslookup” can contact the nameserver, and show the right IP
address:
..120.20.

For example,"ping > www.qnx.com> " returns the right IP address.

4)The name I give “gethostbyname()”, for example, “node1”, is in
“/etc/hosts”,but not in my nameserver. I can’t “nslookup node1” to
resolve
it.

But I can get right response with “ping node1” or “telnet node1”.
In the help documents on QNX, I find the following:
The nslookup utility won’t look at /etc/hosts even if the lookup
keyword
is used in /etc/resolv.conf.

I add “lookup file bind” to “/etc/resolv.conf” according to your
advice,but, “nslookup node1” still can’t find “node1”.

But your “gethostbyname(“node1”)” is succeesed, right? (Cause you could
ping/telnet to “node1”).

nslookup using different resolver as others. It ONLY talk to a
nameserver,
resolving names. Others, ping/telnet, they using the resolver in
libsocket,
which understand “lookup file bind”, menas they will check /etc/hosts
first,
then DNS.

→ xtang@qnx.com

What’s the matter?

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8onccd$4da$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
In my file “/etc/resolv.conf” :
domain nairc.ac.cn
nameserver ..75.90

And, the problem about gethostbyname() still exists either the
netmask
is
set to 255.255.0.0 or to 255.255.255.0.

If you can, post “netstat -ni, netstat -nr”, that will give a
clear picture of the connectivate.

is “ping ..75.90” works?

is “nslookup” contact the nameserver ? Is it showing you the
right
server address (..75.90)

What is "ping " returned ? Is it resolved the name?

The name you giveing “gethostbyname()”, is it in /etc/hosts or
is it in nameserver? Can you "nslookup " to resolve it?

you may consider change your /etc/resolv.conf as:

domain nairc.ac.cn
lookup file bind
nameserver ..75.90

This will tell resolver check /etc/hosts first, if can’t find,
check nameserver.

→ xtang@qnx.com

Ivan Bannon <> ivan.bannon@rjginc.com> > wrote in message
news:8omk1t$obg$> 1@inn.qnx.com> …
Check out the file “/etc/resolv.conf” and be sure it defines your
nameserver
correctly. That may be your problem

Ivan

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote in message
news:8okteh$pvd$> 1@inn.qnx.com> …
On QNX 4.25, I failed to execute function gethostbyname().
I am sure something is wrong with my system configuration,but,
I
can’t
find
it out and correct it.

Thank you for any info.

Zhoujun

\

zhoujun · September 3, 2000, 6:28am

Thank you !
The following is the output of those commands according to your post.

env

_=/usr/bin/env
ABLPATH=/qnx4/photon/translations
PHOTON=//1/dev/photon
KBD=en_US_101.kbd
PATH=/bin:/etc:/usr/bin:/etc:/usr/ucb:/usr/local/bin:/qnx4/photon/bin:
/qnx4/photon/usr/bin:/qnx4/phtk/appbuilder:/usr/bin//photon
SHELL=/bin/sh
PHFONT=/dev/phfont
PHIG=1
PHTK_PATH=/qnx4/phtk
TMPDIR=/tmp
HOME=///
PHWM=pwm
CON_KBD=USA
USER_NAME=/dev/photon
TERM=qansi-m
TZ=wast-08
HZ=1000
ABLANG=en
PHOTON_PATH=/qnx4/photon
PHSTART=1
LOGNAME=root
SYSNAME=qnx4

ping -c1 node1

PING node1.nairc.ac.cn (159.226.75.96): 56 data bytes
64 bytes from 159.226.75.96: icmp_seq=0 ttl=255 time=0 ms

— node1.nairc.ac.cn ping statistics —
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max = 0/0/0 ms

cat test.c

#include <stdio.h>
#include <netdb.h>
main()
{
if(gethostbyname(“node1”)==NULL) printf(“error\n”);

}

cc -o mytest test.c -lsocket

/usr/watcom/10.6/bin/wcc386 -zq -ms -4r -i=/usr/watcom/10.6/usr/include -i=/
usr/include t
est.c
/usr/watcom/10.6/bin/wlink op quiet form qnx flat na mytest op priv=3 op c
libp /usr/watc
om/10.6/usr/lib:/usr/lib:. f /home/empress/test.o l
/usr/watcom/10.6/usr/lib/socket3r.lib
op offset=40k op st=32k

./mytest

error

Xiaodan_Tang1 · September 3, 2000, 3:20pm

zhoujun <jzhou@mail.nairc.ac.cn> wrote:

Thank you !
The following is the output of those commands according to your post.

env

_=/usr/bin/env
ABLPATH=/qnx4/photon/translations
PHOTON=//1/dev/photon
KBD=en_US_101.kbd
PATH=/bin:/etc:/usr/bin:/etc:/usr/ucb:/usr/local/bin:/qnx4/photon/bin:
/qnx4/photon/usr/bin:/qnx4/phtk/appbuilder:/usr/bin//photon
SHELL=/bin/sh
PHFONT=/dev/phfont
PHIG=1
PHTK_PATH=/qnx4/phtk
TMPDIR=/tmp
HOME=///
PHWM=pwm
CON_KBD=USA
USER_NAME=/dev/photon
TERM=qansi-m
TZ=wast-08
HZ=1000
ABLANG=en
PHOTON_PATH=/qnx4/photon
PHSTART=1
LOGNAME=root
SYSNAME=qnx4

ping -c1 node1

PING node1.nairc.ac.cn (159.226.75.96): 56 data bytes
64 bytes from 159.226.75.96: icmp_seq=0 ttl=255 time=0 ms

— node1.nairc.ac.cn ping statistics —
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max = 0/0/0 ms

cat test.c

#include <stdio.h
#include <netdb.h
main()
{
if(gethostbyname(“node1”)==NULL) printf(“error\n”);

}

cc -o mytest test.c -lsocket

/usr/watcom/10.6/bin/wcc386 -zq -ms -4r -i=/usr/watcom/10.6/usr/include -i=/
usr/include t
est.c
/usr/watcom/10.6/bin/wlink op quiet form qnx flat na mytest op priv=3 op c
libp /usr/watc
om/10.6/usr/lib:/usr/lib:. f /home/empress/test.o l
/usr/watcom/10.6/usr/lib/socket3r.lib
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I’m afraid this is the problem.

Check your “/usr/lib/socket3r.lib”, it is supposed to link to
“/usr/tcptk/current/usr/lib/socket3r.lib”. You can try to
compile your program like:

cc -o mytest test.c -L/usr/tcptk/current/usr/lib -lsocket

I bet this time it will work.

The “socket3r.lib” library is belong to TCPTK package. But in
old QNX (qnx 4.24?) system, an old “socket3r.lib” in watcom c dev
package will overwrite the link.

-xtang@qnx.com

op offset=40k op st=32k

./mytest

error

zhoujun · September 4, 2000, 2:49am

Thank you !
Now, I have moved the file “/usr/watcom/10.6/usr/lib/socket3r.lib” to file
“/usr/watcom/10.6/usr/lib/socket3r.bk.lib” . After I compile file “test.c”
with “cc -o mytest test.c -lsocket”, “./mytest” can return right result.

But, when I install a database software written by Empress Software Inc.,the
error “*** System Error *** gethostbyname() failed” still appears.

By the way,“node1” is my hostname.

Xiaodan Tang <xtang@qnx.com> wrote in message
news:8otq8h$ri5$1@nntp.qnx.com…

zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
The following is the output of those commands according to your post.

env

_=/usr/bin/env
ABLPATH=/qnx4/photon/translations
PHOTON=//1/dev/photon
KBD=en_US_101.kbd
PATH=/bin:/etc:/usr/bin:/etc:/usr/ucb:/usr/local/bin:/qnx4/photon/bin:
/qnx4/photon/usr/bin:/qnx4/phtk/appbuilder:/usr/bin//photon
SHELL=/bin/sh
PHFONT=/dev/phfont
PHIG=1
PHTK_PATH=/qnx4/phtk
TMPDIR=/tmp
HOME=///
PHWM=pwm
CON_KBD=USA
USER_NAME=/dev/photon
TERM=qansi-m
TZ=wast-08
HZ=1000
ABLANG=en
PHOTON_PATH=/qnx4/photon
PHSTART=1
LOGNAME=root
SYSNAME=qnx4

ping -c1 node1

PING node1.nairc.ac.cn (159.226.75.96): 56 data bytes
64 bytes from 159.226.75.96: icmp_seq=0 ttl=255 time=0 ms

— node1.nairc.ac.cn ping statistics —
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max = 0/0/0 ms

cat test.c

#include <stdio.h
#include <netdb.h
main()
{
if(gethostbyname(“node1”)==NULL) printf(“error\n”);

}

cc -o mytest test.c -lsocket

/usr/watcom/10.6/bin/wcc386 -zq -ms -4r -i=/usr/watcom/10.6/usr/include -i=/
usr/include t
est.c
/usr/watcom/10.6/bin/wlink op quiet form qnx flat na mytest op priv=3 op
c
libp /usr/watc
om/10.6/usr/lib:/usr/lib:. f /home/empress/test.o l
/usr/watcom/10.6/usr/lib/socket3r.lib
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I’m afraid this is the problem.

Check your “/usr/lib/socket3r.lib”, it is supposed to link to
“/usr/tcptk/current/usr/lib/socket3r.lib”. You can try to
compile your program like:

cc -o mytest test.c -L/usr/tcptk/current/usr/lib -lsocket

I bet this time it will work.

The “socket3r.lib” library is belong to TCPTK package. But in
old QNX (qnx 4.24?) system, an old “socket3r.lib” in watcom c dev
package will overwrite the link.

→ xtang@qnx.com

op offset=40k op st=32k

./mytest

error

Xiaodan_Tang1 · September 4, 2000, 4:55am

zhoujun <jzhou@mail.nairc.ac.cn> wrote:

Thank you !
Now, I have moved the file “/usr/watcom/10.6/usr/lib/socket3r.lib” to file
“/usr/watcom/10.6/usr/lib/socket3r.bk.lib” . After I compile file “test.c”
with “cc -o mytest test.c -lsocket”, “./mytest” can return right result.

But, when I install a database software written by Empress Software Inc.,the
error “*** System Error *** gethostbyname() failed” still appears.

By the way,“node1” is my hostname.

So this database software is static linking with old library.
With old gethostbyname(), you only have 2 choice:

add “node1” into your name server, so while gethostbyname() checked
nameserver, it will got a successful reply.

or

remove /etc/resolv.conf file. Thus gethostbyname() will only check
/etc/hosts and resolve “node1”.

-xtang@qnx.com

Xiaodan Tang <> xtang@qnx.com> > wrote in message
news:8otq8h$ri5$> 1@nntp.qnx.com> …
zhoujun <> jzhou@mail.nairc.ac.cn> > wrote:
Thank you !
The following is the output of those commands according to your post.

env

_=/usr/bin/env
ABLPATH=/qnx4/photon/translations
PHOTON=//1/dev/photon
KBD=en_US_101.kbd
PATH=/bin:/etc:/usr/bin:/etc:/usr/ucb:/usr/local/bin:/qnx4/photon/bin:
/qnx4/photon/usr/bin:/qnx4/phtk/appbuilder:/usr/bin//photon
SHELL=/bin/sh
PHFONT=/dev/phfont
PHIG=1
PHTK_PATH=/qnx4/phtk
TMPDIR=/tmp
HOME=///
PHWM=pwm
CON_KBD=USA
USER_NAME=/dev/photon
TERM=qansi-m
TZ=wast-08
HZ=1000
ABLANG=en
PHOTON_PATH=/qnx4/photon
PHSTART=1
LOGNAME=root
SYSNAME=qnx4

ping -c1 node1

PING node1.nairc.ac.cn (159.226.75.96): 56 data bytes
64 bytes from 159.226.75.96: icmp_seq=0 ttl=255 time=0 ms

— node1.nairc.ac.cn ping statistics —
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max = 0/0/0 ms

cat test.c

#include <stdio.h
#include <netdb.h
main()
{
if(gethostbyname(“node1”)==NULL) printf(“error\n”);

}

cc -o mytest test.c -lsocket

/usr/watcom/10.6/bin/wcc386 -zq -ms -4r -i=/usr/watcom/10.6/usr/include -i=/
usr/include t
est.c
/usr/watcom/10.6/bin/wlink op quiet form qnx flat na mytest op priv=3 op
c
libp /usr/watc
om/10.6/usr/lib:/usr/lib:. f /home/empress/test.o l
/usr/watcom/10.6/usr/lib/socket3r.lib
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I’m afraid this is the problem.

Check your “/usr/lib/socket3r.lib”, it is supposed to link to
“/usr/tcptk/current/usr/lib/socket3r.lib”. You can try to
compile your program like:

cc -o mytest test.c -L/usr/tcptk/current/usr/lib -lsocket

I bet this time it will work.

The “socket3r.lib” library is belong to TCPTK package. But in
old QNX (qnx 4.24?) system, an old “socket3r.lib” in watcom c dev
package will overwrite the link.

→ xtang@qnx.com

op offset=40k op st=32k

./mytest

error