libqwt.so.6: cannot open shared object file: No such file or directory

[jiapei100]

Hi, all:

Environment: Ubuntu 13.04 + qt5 (from repository) + qwt 6.1.0
I successfully build qwt and put everything down to /opt/qwt

The library files are

pei@pei-Latitude-E6410:/opt/qwt$ ls lib
libqwt.so libqwt.so.6 libqwt.so.6.1 libqwt.so.6.1.0
pei@pei-Latitude-E6410:/opt/qwt$ ls plugins/designer/
libqwt_designer_plugin.so


However, when I tried to link libqwt, I got the following error message

error while loading shared libraries: libqwt.so.6: cannot open shared object file: No such file or directory

And, the variables $PATH and $LD_LIBRARY_PATH are as follows:

pei@pei-Latitude-E6410:~$ echo $PATH
/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/opt/qwt/lib:/opt/qwt/plugins/designer
pei@pei-Latitude-E6410:~$ echo $LD_LIBRARY_PATH
/usr/lib/vtk-5.10:/opt/qwt/lib:/opt/qwt/plugins/designer


Where am I wrong?


Cheers
Pei

[BrFla]

I had the same problem....
I put the answer in http://www.qtcentre.org/threads/55513-How-to-pick-the-line-of-a-curve-(Pt-BR-Como-pegar-a-linha-de-uma-curva-)

[Uwe]

Guess you are talking about an problem when trying to start your application: try "ldd yourapplication" in the same shell, where you have set the LD_LIBRARY_PATH like above.

Uwe