I think by default linkxlC gets installed at /opt/IBM/xlC/13.1.0/bin/linkxlC
Either you want to add /opt/IBM/xlC/13.1.0/bin path in your PATH environment or give absolute path.
Regarding your other question.. are you asking if you can install rpm packages in a different directory than specified by rpm package ?
If that is for AIX and packages are from AIX toolbox it is not supported. The rpm packages are not relocatable.
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SANKET RATHI
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