As with any standard C library, D-ISAM is fully supported in Apple Xcode and therefore Swift as covered in Using Swift with Cocoa and Objective-C.

Pure C libraries like D-ISAM and the system libraries are core components of Objective-C, and are imported in the same way (but without most of the fuss) and the real details are covered in Interacting with C APIs.

Building D-ISAM in the Xcode IDE is a guide to working with D-ISAM in the Xcode Integrated Developer Environment, while Building D-ISAM in Xcode from the command line covers the manual installation details.

For quite sensible reasons, Swift Strings will not convert directly to character pointer arrays, unless these are declared as constant, and unfortunately the current D-ISAM library does not include this syntax, although it should. An Update for Constant Chars is available.