c - Array of Swift Strings into const char * const * -

i having trouble converting array of swift strings array c function signature:

pgconn *pqconnectstartparams(const char * const *keywords, const char * const *values, int expand_dbname) 

in swift, const char * const * shows as:

<unsafepointer<unsafepointer<int8>> 

so try convert contents of dictionary [string:string] called 'options' , feed function follows:

var keys = [[int8]]() var values = [[int8]]() (key, value) in options {     var int8array = key.cstringusingencoding(nsutf8stringencoding)!     keys.append(int8array)     int8array = value.cstringusingencoding(nsutf8stringencoding)!             values.append(int8array) } pgconnection = pqconnectstartparams(unsafepointer(keys), unsafepointer(values), 0) 

it compiles , runs, function not work.

any insight appreciated.

that's not perfect @ least works.

let options = ["key1": "value1", "key2": "value2", "key3": "value3", "key4": "value4"]  var keys = [string]()  (key, value) in options {      keys.append(key) }  //you need identify how many paramenters should provided , set them following "static way" //i did not find how prepare dynamically let ckey1 = keys[0].cstringusingencoding(string.defaultcstringencoding())! let key1pointer = unsafepointer<cchar>(ckey1)  let ckey2 = keys[1].cstringusingencoding(string.defaultcstringencoding())! let key2pointer = unsafepointer<cchar>(ckey2)  let ckey3 = keys[2].cstringusingencoding(string.defaultcstringencoding())! let key3pointer = unsafepointer<cchar>(ckey3)  let ckey4 = keys[3].cstringusingencoding(string.defaultcstringencoding())! let key4pointer = unsafepointer<cchar>(ckey4)   let keyscarray = [key1pointer, key2pointer, key3pointer, key4pointer]  f(keyscarray)  /*  c - code   void f(const char * const *keywords) {   printf("%s\n", keywords[0]);  printf("%s\n", keywords[1]);  printf("%s\n", keywords[2]);  printf("%s\n", keywords[3]);   }  */ 

hope helps. can share sample app if want.