module Procord_worker:sig..end
The easiest way to build a worker is just to use run. If you prefer
to handle command-line options yourself, use other run_* functions.
type
Procord_task.worker_task, but allowing heterogenous lists of
tasks.val task : ('a, 'b) Procord_task.worker_task -> task
val run : ?spec:(Arg.key * Arg.spec * Arg.doc) list ->
?usage:Arg.usage_msg ->
?anon:Arg.anon_fun -> task list -> unitThis function parses command line options as follows:
--procord-worker: execute one task, communicating over stdin
and stdout, and exit;--procord-input-file <file>: option for --procord-worker which tells
the worker to read inputs from <file> instead of stdin;--procord-output-file <file>: option for --procord-worker which
tells the worker to write outputs from <file> instead of stdout;--procord-server: listen for TCP connections and execute one task
per connection;--procord-hostname <hostname>: option for --procord-server which
specifies the IPv4/IPv6/DNS address to listen to (default 0.0.0.0);--procord-port <port>: option for --procord-server which
specifies the port to listen to (default 1111);--procord-max-simultaneous-tasks <count>:
option for --procord-server which specifies the maximum number of
tasks that may be executed at the same time;--procord-reuse-address:
option for --procord-server which tells the server to set the
SO_REUSEADDR option on the listening socket;--procord-dont-fork:
option for --procord-server which removes the call to
Unix.fork, imlying that only one task can be executed at the same
time and that crashing a task crashes the server as well.--procord-worker nor --procord-server are given, the
function returns immediately. Else, the function never returns. Thus
you may call run before your main program starts to allow your
program to act both as the main program and as a worker.
The worker will be able to run any of the tasks given in the last argument.
You should not call Arg.parse yourself (nor Arg.align).
Instead, pass your specifications using spec, usage and anon.
If you need more complex command-line parsing, use the
other run_* functions.
val get_input_file : unit -> string--procord-input-file argument.
Default value is "".val set_input_file : string -> unit--procord-input-file argument.val get_output_file : unit -> string--procord-output-file argument.
Default value is "".val set_output_file : string -> unit--procord-output-file argument.val get_hostname : unit -> string--procord-hostname argument.
Default value is "".val set_hostname : string -> unit--procord-hostname argument.val get_port : unit -> int--procord-port argument.
Default value is 1111.val set_port : int -> unit--procord-port argument.val get_max_simultaneous_tasks : unit -> int option--procord-max-simultaneous-tasks argument.
Default value is None (infinite).val set_max_simultaneous_tasks : int option -> unit--procord-max-simultaneous-tasks argument.val get_reuse_address : unit -> bool--procord-reuse-address argument.
Default value is false.val set_reuse_address : bool -> unit--procord-reuse-address argument.val get_dont_fork : unit -> bool--procord-dont-fork argument.
Default value is false.val set_dont_fork : bool -> unit--procord-dont-fork argument.val run_custom : ?input:Unix.file_descr ->
?output:Unix.file_descr -> task list -> unitinput : File descriptor for reading. Default Unix.stdin.output : File descriptor for writing. Default Unix.stdout.
The last parameter is the list of tasks that the worker can handle.
val run_listen : ?continue:(unit -> bool) ->
?accept:(Unix.sockaddr -> bool) ->
?max_simultaneous_tasks:int ->
?reuse_address:bool ->
?dont_fork:bool ->
hostname:string -> port:int -> task list -> unitcontinue : Function called before each call to
Unix.accept. If it returns false, the worker stops
accepting new connections, and will exit after all tasks are
executed. If unspecified, run_listen never returns.accept : Function called after each call to Unix.accept.
It is given the remote address of the new connection.
If it returns false, the connection is closed immediately.max_simultaneous_tasks : The maximum number of tasks that
the server may execute at the same time. On Windows, only one
task can be executed at the same time (no fork).reuse_address : If true, set SO_REUSEADDR, preventing the
"Address already in use" error. This is useful for debugging but
could potentially be abused by malware.dont_fork : If true, do not fork to run the tasks.hostname : Specifies the interface to listen to. Examples:"localhost": only accept local IPv4 connections;"::1": only accept local IPv6 connections;"0.0.0.0": accept all IPv4 connections;"::": accept all IPv6 connections.port : Specifies the port to listen to.
Raise Unix_error if the server cannot be established.
stdout as, in local mode,
workers communicate with the main program using stdout. In remote
mode, workers communicate with the main program using sockets, and
writing on stdout is not an issue. However, this will print on the
standard output of the worker, not of the main program.
Using the functions below allows you to continue using the
Format module normally. Everything you write will actually be
printed by the main program. This allows you to write your tasks
as if they were running in the main program process.
The functions below have no effect on the input/output functions
of Pervasives, Unix, Printf and Scanf.
val redirect_standard_formatters : unit -> unitFormat.std_formatter and Format.err_formatter to the main
program.
Everything you write to Format.std_formatter (for example using
Format.printf) will be sent to the main program, which will print
it on its own stdout.
Similarly, everything you write to Format.err_formatter (for
example using Format.eprintf) will be sent to the main program,
which will print it on its own stderr.
This function is automatically called by Procord_worker.run, but not by
other run_* functions.
You may call this function from the main program, typically
before calling a run_* function, or from a task. The
redirection will continue if the main program becomes a
worker.
val redirect_formatter : Format.formatter -> Procord_protocol.print_destination -> unitEverything you write to the formatter given in argument will be redirected to the specified destination of the main program.
You may call this function from the main program, typically
before calling a run_* function, or from a task. The
redirection will continue if the main program becomes a
worker.
val make_redirected_formatter : Procord_protocol.print_destination -> Format.formatter