topic Re: Can't open shared library in Operating System - HP-UX

Can't open shared library

bivian — Sun, 14 Feb 2010 13:36:26 GMT

If the loader gives following error
"Can't open shared library: ..."
what does it indicate?

The shared library has been linked with +s and +b options. The SHLIB_PATH has been set properly.
Is there anything else that is missing?

Re: Can't open shared library

Dennis Handly — Mon, 15 Feb 2010 06:23:59 GMT

>"Can't open shared library:" what does it indicate?

Does it give a reason?

>Is there anything else that is missing?

Have you done the same to the executable?
What HP-UX version and architecture are you using?

Re: Can't open shared library

bivian — Mon, 15 Feb 2010 07:44:38 GMT

No i don't see any reason.

I have done the same thing for executable also.

I am HPUX PARISC64. Following are details from uname command:
"HP-UX B.11.23 9000/800"

Re: Can't open shared library

bivian — Mon, 15 Feb 2010 07:46:35 GMT

Just to add the executable and the shared library are both linked on one machine and are being used in another machine.

Re: Can't open shared library

Dennis Handly — Mon, 15 Feb 2010 08:01:41 GMT

>No I don't see any reason.

No errno text in the message? What was the complete message?

What does "ldd executable" show?
You may have to use "tusc -fp -ea -o tusc.out executable" to trace what's happening.

Re: Can't open shared library

bivian — Tue, 16 Feb 2010 09:06:22 GMT

I am not sure which executable is trying to load the shared library. The error message "Can't open shared library libclntsh.so" is logged into the log files.

tusc command shows some useful information.

From tusc.out i see that it finds the library in one location and open call succeeds. But later the open on the same library fails. tusc.out shows something like this:

.....
.....
[4268] open("/home/prash/lib32/libclntsh.sl", O_RDONLY, 0200) =
[4268] fstat(3, 0x77ff4748) .............................. = 0
[4268] read(3, "0210010e0512@ \0K i 5 s \0\0\0\0".., 128) = 128
[4268] lseek(3, 128, SEEK_SET) ........................... = 128
[4268] read(3, "10\0\004\0\0\0( \0c + d4\0\010\0".., 48) . = 48
[4268] read(3, "80\0\0\v\0\0\004\0\0\0\0", 12) ........... = 12
[4268] mmap(NULL, 6500352, PROT_READ|PROT_EXEC, MAP_SHARED|MAP_SHLIB, 3, 1757184
) = 0xcd400000
[4268] mmap(NULL, 8192, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOU
S|MAP_SHLIB, -1, 0) = 0x77ddd000
.....
....

[4336] open("/home/prash/lib32/libnmemso.sl", O_RDONLY, 0200) =
[4334] close(3638) ....................................... ERR#9 EBADF
[4336] fstat(3, 0x77ff49c8) .............................. = 0
[4334] close(3639) ....................................... ERR#9 EBADF
[4336] read(3, "0210010e0512@ \0K i 5 s \0\0\0\0".., 128) = 128

Re: Can't open shared library

bivian — Tue, 16 Feb 2010 09:07:43 GMT

The second entry in tusc.out is also for libclntsh.so...

Re: Can't open shared library

ranganath ramachandra — Tue, 16 Feb 2010 10:01:58 GMT

Please attach the complete tusc trace that you get from
tusc -s open,read,close,mmap,munmap,stat,fstat -fp -ea -o tusc.out executable

Re: Can't open shared library

Dennis Handly — Tue, 16 Feb 2010 16:03:58 GMT

>I am not sure which executable is trying to load the shared library.

It should be obvious. You should know your application. And tusc will tell you:
tusc -fp -ea -o tusc.out application ...
(Are you using threads?)

>But later the open on the same library fails.

This isn't really later on, this is a separate process. And the shlib is different.

>[4268] open("/home/prash/lib32/libclntsh.sl", O_RDONLY, 0200) =

(Please make sure you provide the return values.)

[4336] open("/home/prash/lib32/libnmemso.sl", O_RDONLY, 0200) =
[4334] close(3638) . ERR#9 EBADF
[4336] fstat(3, 0x77ff49c8) . = 0
[4334] close(3639) . ERR#9 EBADF
[4336] read(3, "0210010e0512@
> The second entry in tusc.out is also for libclntsh.so.

Huh? It says libnmemso.sl.

Are these PIDs or thread IDs?

Re: Can't open shared library

bivian — Sat, 20 Feb 2010 04:42:21 GMT

Sorry for the delayed reply..

I have run the command "tusc -s open,read,close,mmap,munmap,stat,fstat -fp -ea -o tusc.out" on the process id.
It gives out a huge file which i cannot paste here.
Can you please tell me what parts of the file i need to paste.

Re: Can't open shared library

Dennis Handly — Sat, 20 Feb 2010 05:05:10 GMT

>It gives out a huge file which i cannot paste here.

Have you tried gzip on it?

>Can you please tell me what parts of the file I need to paste.

Basically only the process with the error. And only the parts where the error occurs and enough history to see what's going on.

Re: Can't open shared library

bivian — Sat, 20 Feb 2010 05:28:54 GMT

Thanks.
I did not realize that we can attach files. I have zipped and attached the output file.

Btw, please ignore the error messages that i mentioned above...The following is the error logged in error logs of application:

Could not load library '/home/prash/newdb/lib32/libnmcfsga.sl' for reason 'Can't open shared library: libnmemso.sl'

Re: Can't open shared library

Dennis Handly — Sat, 20 Feb 2010 08:43:18 GMT

>The following is the error logged in error logs of application:
>Could not load library '/home/prash/newdb/lib32/libnmcfsga.sl' for reason 'Can't open shared library: libnmemso.sl'

I see that several times. libnmemso.sl must be a dependent shlib with no particular path??

Please provide the output of "chatr /home/prash/newdb/lib32/libnmcfsga.sl".

The processes 28914, 28929, 28954 & 28958 are using libjvm.sl. Which dlopens(?) /home/prash/newdb/lib32//libnmemso.sl.

Is this the one you want?
Also, it would be helpful if you also included the exec system call:
-s open,read,close,mmap,munmap,stat,fstat,exec

Re: Can't open shared library

bivian — Sun, 21 Feb 2010 03:03:50 GMT

Chatr output of libnmcfsga.sl:
libnmcfsga.sl:
shared library
shared library dynamic path search:
SHLIB_PATH enabled first
embedded path disabled second Not Defined
shared library list:
dynamic libnmemso.sl
dynamic libjava.sl
dynamic libjvm.sl
dynamic /usr/lib/libcl.2
dynamic /usr/lib/librt.2
dynamic /usr/lib/libpthread.1
dynamic /usr/lib/libnss_dns.1
dynamic /usr/lib/libdld.2
dynamic /usr/lib/libnsl.1
dynamic /usr/lib/libm.2
shared vtable support disabled
explicit unloading enabled
runtime checks disabled
static branch prediction disabled
executable from stack: D (default)
kernel assisted branch prediction enabled
lazy swap allocation disabled
text segment locking disabled
data segment locking disabled
third quadrant private data space disabled
fourth quadrant private data space disabled
third quadrant global data space disabled
data page size: D (default)
instruction page size: D (default)
nulptr references disabled
shared library private mapping disabled

Yes, libnmemso.so belongs to the directory /home/prash/newdb/lib32/. This is the one that is not loading.

Please see the attached tusc1.out which contains exec system call also.

Re: Can't open shared library

Dennis Handly — Sun, 21 Feb 2010 04:49:43 GMT

>SHLIB_PATH enabled first
>shared library list: dynamic libnmemso.sl

This says that if SHLIB_PATH contains m/home/prash/newdb/lib32, it should work.

What is the tusc command you are using? Why do we see other processes besides 25326, emagent? Can we start tusc on emagent and not attach after it starts?
Is emagent a SETUID process?
Why does 25326 keep going after the error? (We only need to see the error once.)
Is SHLIB_PATH before emagent starts?

>tusc1.out which contains exec system call also.

Please also include fork & exit.

Re: Can't open shared library

bivian — Mon, 22 Feb 2010 23:58:42 GMT

I was using the command - tusc -s open,read,close,mmap,munmap,stat,fstat,exec -ea -o tusc.out" on the process id.

No, it is not SETUID process.

I have use the following command now:
tusc -fp -ea -o tusc.out
Please see the uploaded output in tusc2.out.

Re: Can't open shared library

Horia Chirculescu — Tue, 23 Feb 2010 06:31:47 GMT

Hello,

stat("/usr/lib/libnmemso.sl", 0x778410d0) ........ ERR#2 ENOENT

You could make a soft link of the library in the /usr/lib directory

ln -sf /home/prash/newdb/lib32/libnmemso.sl /usr/lib/libnmemso.sl

Or... maybe you have some problem with SHLIB_PATHS ? (the path to the libnmemso.sl library is listed three times, should be only one).

SHLIB_PATH=/home/prash/newdb/jdk/jre/lib/PA_RISC2.0/hotspot:/home/prash/newdb/jdk/jre/lib/PA_RISC2.0:/home/prash/newdb/lib32:/home/prash/newdb/network/lib32:/home/prash/newdb/perl/lib:/home/prash/newdb/lib32:/home/prash/newdb/oui/lib/HP-UX:/home/prash/newdb/lib32

Horia.

Re: Can't open shared library

Dennis Handly — Tue, 23 Feb 2010 06:46:11 GMT

>Please see the uploaded output in tusc2.out.

Unless you can get your /home/prash/newdb/bin/emagent process to print out its SHLIB_PATH, we can only assume it doesn't have /home/prash/newdb/lib32?

Note: SHLIB_PATH must be set before emagent starts, not just before the dlopen/shl_load.

What linker/dld patches do you have?

Re: Can't open shared library

bivian — Tue, 23 Feb 2010 11:14:41 GMT

I will investigate whether the SHLIB_PATH is being set or not.

The linker patch i am using is phss_39821.

Re: Can't open shared library

Dennis Handly — Wed, 24 Feb 2010 08:34:55 GMT

>The linker patch I am using is PHSS_39821.

That is the recommended patch, there is a later one: PHSS_40537