Editing DOS/360 and successors (section)

===Application programming interface===
The DOS/360 [[application programming interface]] was incompatible with OS/360.  [[High level language]] programs written for DOS needed to be compiled and linked before they could be used with OS/360. Minor differences between compilers of DOS as opposed to OS sometimes required modifications to programs. The port in the other direction however was more challenging. Since OS/360 had significantly more features supported in its API, any use of those features would have to be removed from programs being ported to DOS. This was less of a problem for programmers working in [[high level language]]s such as [[COBOL]].  [[Assembly language|Assembler]] programs, on the other hand, tended to utilize those very features more often and usually needed greater modification to run on DOS.