I've written a windows dll in Haskell. The calling program is written in Delphi (pascal). I want to profile this dll. Because you don't have a command line in a dll for +RTS. -RTS, I call the dll with hs_init_ghc (a exported function in the dll). I had to translate some parts of rtsopts.h to Delphi. Everyting seems okay. The program does not hang, no catastrophic failures. When I start with the parameter for rtsoptions in hs_init_ghc I get: with -t --machine-readable ->machine readable overview on the screen. with -B sounds the bell with each garbage collection, and also --info works as expected. But when I call hs_init_ghc with rtsoptions -h I get 3 lines with on each line: Can't open profiling report file <unknown>.hp. With -p I get missing profiling report <unknown>.prof Any idea what I'am doing wrong? Kees