if getting linker error like:
ld: 0711-781 ERROR: TOC overflow. TOC size: 67120 Maximum size: 65536
supply to it -bbigtoc option (e.g. -Wl,-bbigtoc to gcc).
(sort of) substitute for ldd: dump -H
substitutes for nfs mount and umount
instead of $LD_LIBRARY_PATH, use $LIBPATH (same on AIX)
filesystem inside /QOpenSys is case-sensitive, outside it - case insensitive.