Short answer: SAS code written on one platform will usually work unchanged on another platform.
Longer answer: there are some issues in the migration that require experience on both platforms and can affect a number of areas of existing programs. The issue is broad, and doesn't belong to this forum, although the first apparent issue will be that MS Office programs work only on Windows and there may be some issues of integration with MS Office when the program is run on a platform other than Windows. Workarounds for these issues are far too complex for discussion here, but searching for user papers from the SAS conferences on support.sas.com will turn up many discussions on how particular elements of a migration were resolved.
Kind regards
David
