Docs GODI Archive
Projects Blog Knowledge

Look up function:

(e.g. "List.find" or "keysym")
More options

Module Shell_uq


module Shell_uq: sig .. end
Run shell commands within Unixqueues


This module is not thread-safe. See the module Shell_sys for more information.

Signal handlers: It is important to have a number of signal handlers installed for proper function of the engines. It is recommended to call the pair of functions Shell_sys.configure_job_handlers and Shell_sys.install_job_handlers for this purpose. This is not done automatically.

Note that this has a global side effect on the whole process, because there is only one set of signal handlers.

Engines


class type ['a] job_handler_engine_type = object .. end
This type of engine also returns the job and the job_instance.
class call_engine : ?ignore_error_code:bool -> ?mode:Shell_sys.group_mode -> ?stdin:Shell.producer -> ?stdout:Shell.consumer -> ?stderr:Shell.consumer -> Shell_sys.command list -> Unixqueue.event_system -> [Shell_sys.job_status] job_handler_engine_type
This engine corresponds to Shell.call.

Examples

All examples presented for the Shell module can be easily rewritten for Shell_uq. For example, to call "ls" and collect the result in a buffer, use this piece of code:

 let ues = Unixqueue.create_unix_event_system();;
 let b = Buffer.create 10;;
 let e = new call_engine ~stdout:(Shell.to_buffer b) [ Shell.command "ls" ];;
 Unixqueue.run ues;;
 let r = Buffer.contents b;;
 

This means, one simply creates a call_engine instead of invoking Shell.call, and then runs the queue. Note that you must look at e#state to find out whether the engine e produced an error, no exception is raised in this case.

It is allowed (and somehow the purpose of this module) to create several job engines, and let them run in parallel.

This web site is published by Informatikbüro Gerd Stolpmann
Powered by Caml