Run shell commands within Unixqueues
This module is not thread-safe. See the module
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.install_job_handlers for this purpose. This is not
Note that this has a global side effect on the whole process, because there is only one set of signal handlers.
This type of engine also returns the
job and the
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 ->
This engine corresponds to
All examples presented for the
Shell module can be easily rewritten
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.