[lug] A head scratcher for your weekend

[Matt Bidwell]

Unfortunatly they both appear to be 64bit and there only is one version 
of libQt5Core.

# file /usr/bin/mythbackend
/usr/bin/mythbackend: ELF 64-bit LSB pie executable x86-64, version 1 
(GNU/Linux), dynamically linked, interpreter 
/lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, 
BuildID[sha1]=293e8e4f8ef60e3a1d9a0133b50070cc837d008c, stripped
# file /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.10.1
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5.10.1: ELF 64-bit LSB shared 
object x86-64, version 1 (GNU/Linux), dynamically linked, interpreter 
/lib64/ld-linux-x86-64.so.2, 
BuildID[sha1]=29089e33a2458624bd5d495a5698237fedaa2a91, for GNU/Linux 
3.17.0, stripped


LD_LIBRARY_PATH was low hanging fruit that I already checked out leaving...
RPATH and RUNPATH which I'm less sure how to hunt down.
#readelf --dynamic /usr/bin/mythbackend | grep PATH
returns nothing but web examples show me that I should get both a hit on 
RPATH and RUNPATH.

Thanks for the response.

On 05/19/2018 06:29 AM, Davide Del Vento wrote:
> Often a 32 vs 64 bit causes this problem. Try
> 
> file /usr/bin/mythbackend
> 
> file /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.10.1
> 
> and make sure they are both 64 bit (assuming that the directory name
> for libQt5Core.so is correct).
> 
> Also check LD_LIBRARY_PATH, RPATH, RUNPATH and /etc/ld.so.conf and
> make sure there isn't another location with higher priority than
> /usr/lib/x86_64-linux-gnu/ containing a file called libQt5Core.so.5
> (which again, could have 32/64 bit mismatch or be a broken link or
> something).
> 
> HTH
> Davide
> 
> On Sat, May 19, 2018 at 5:28 AM, Matt Bidwell <mbidwell at gmail.com> wrote:
>> Library is installed, program can find other libraries in that directory.
>> Reinstalling or downgrading either the package or the library didn't fix
>> it.... What could have happened to my system?
>> # ls -alh /usr/lib/x86_64-linux-gnu/libQt5Core.so.5*
>> lrwxrwxrwx 1 root root   20 May 12 07:03
>> /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 -> libQt5Core.so.5.10.1
>> lrwxrwxrwx 1 root root   20 May 12 07:03
>> /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.10 -> libQt5Core.so.5.10.1
>> -rw-r--r-- 1 root root 5.0M May 12 07:03
>> /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.10.1
>>
>> ldd /usr/bin/mythbackend
>> ...
>>          libQt5Script.so.5 => /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
>> (0x00007f4eb42f8000)
>>          libQt5Core.so.5 => not found
>>          libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0
>> (0x00007f4eb40d8000)
>> ...
>>
>> This is very perplexing.
>> _______________________________________________