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.
class type['t]
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
.
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.