Convert a Swift Array of String to a to a C string array pointer

You can proceed similarly as in How to pass an array of Swift strings to a C function taking a char ** parameter. It is a bit different because of the different const-ness of the argument array, and because there is a terminating nil (which must not be passed to strdup()).

This is how it should work:

let array: [String?] = ["name1", "name2", nil]

// Create [UnsafePointer<Int8>]:
var cargs = array.map { $0.flatMap { UnsafePointer<Int8>(strdup($0)) } }
// Call C function:
let result = command(&cargs)
// Free the duplicated strings:
for ptr in cargs { free(UnsafeMutablePointer(mutating: ptr)) }