I am running preproc-sess command on Linux Debian. The thing is it shows error msg like '3dvolreg.afni error while loading shares library :libXp.so.6. No such file or directory. After I installed the libXp.so.6, other lib like libpng is required. 

I am wondering what might be the causes, and how to fix it. If it is indeed the problem of libs, can I have a list of the dependent libraries for that command? 

Best regards,

Zoe