(** QMC=Chem installation directory *) let root = lazy ( try Sys.getenv "QMCCHEM_PATH" with | Not_found -> failwith "QMCCHEM_PATH environment variable not set" ) (* PATH environment variable as a list of strings *) let path = lazy ( let p = try Sys.getenv "PATH" with | Not_found -> failwith "PATH environment variable is not set" in String.split_on_char ':' p ) (* Full path of a binary taken from the PATH *) let full_path exe = let rec in_path_rec = function | [] -> None | head :: tail -> begin let fp = Filename.concat head exe in if Sys.file_exists fp then Some fp else in_path_rec tail end in Lazy.force path |> in_path_rec (* True if an executable is in the PATH *) let in_path x = match full_path x with | Some _ -> true | None -> false let has_parallel = lazy( in_path "parallel" ) let has_mpirun = lazy( in_path "mpirun" ) let has_srun = lazy( in_path "parallel" ) let has_qmc = lazy( in_path "qmc" ) let mpirun = lazy ( try Sys.getenv "QMCCHEM_MPIRUN" with | Not_found -> "mpirun" ) let qmcchem = lazy( Filename.concat (Lazy.force root) "bin/qmcchem" ) and qmc = lazy( Filename.concat (Lazy.force root) "bin/qmc" ) and qmcchem_info = lazy( Filename.concat (Lazy.force root) "bin/qmcchem_info" ) and qmc_create_walkers = lazy( Filename.concat (Lazy.force root) "bin/qmc_create_walkers" ) let dev_shm = "/dev/shm/" (** Name of the host on which the data server runs *) let hostname = lazy ( try Unix.gethostname () with | _ -> "127.0.0.1" ) external get_ipv4_address_for_interface : string -> string = "get_ipv4_address_for_interface" let ip_address = lazy ( let interface = try Some (Sys.getenv "QMCCHEM_NIC") with Not_found -> None in match interface with | None -> begin try let host = Lazy.force hostname |> Unix.gethostbyname in Unix.string_of_inet_addr host.h_addr_list.(0); with | Unix.Unix_error _ -> failwith "Unable to find IP address from host name." end | Some interface -> let result = get_ipv4_address_for_interface interface in if String.sub result 0 5 = "error" then Printf.sprintf "Unable to use network interface %s" interface |> failwith else result )