% MINERVA (c) IF Computer  1996,97
% http://www.ifcomputer.com/MINERVA   mailto:support@ifcomputer.com

:- package('ExecExtension').
:- package('line_io').

% system_lines(+Command,-Lines) <-
% NOTE: this works only if the stream is terminated with end_of file character
system_lines(Command,Lines) :-
	system_lines(Command,_ExitValue,Lines).

% system_lines(+Command,-ExitValue,-Lines) <-
% NOTE: this works only if the stream is terminated with end_of file character
% and only if the stream is available fast enough
system_lines(Command,ExitValue,Lines) :-
	process_exec(Command,Process,StreamToCmd,StreamFromCmd,ErrorsFromCmd),
	close(StreamToCmd),
	readLines(StreamFromCmd,Lines),
	waitFor(Process,_WaitValue),
	exitValue(Process,ExitValue),
	close(StreamFromCmd),
	close(ErrorsFromCmd).

% system(-Command) <-
system(Command) :-
	system(Command,_ExitValue).

% system(+Command,-ExitValue) <-
system(Command,ExitValue) :-
	process_exec(Command,Process,StreamToCmd,StreamFromCmd,ErrorsFromCmd),
	close(StreamToCmd),
	waitFor(Process,_WaitValue),
	exitValue(Process,ExitValue),
	close(StreamFromCmd),
	close(ErrorsFromCmd).

% process_exec(+Command,-Process,-StreamToCmd,-StreamFromCmd,-ErrorsFromCmd) <-
process_exec(Command,Process,StreamToCmd,StreamFromCmd,ErrorsFromCmd) :-
	process_exec_async(Command,Process,StreamToCmd,StreamFromCmd,ErrorsFromCmd),
	!.

% process_exec_async(+Command,-Process,-StreamToCmd,-StreamFromCmd,-ErrorsFromCmd) <-
process_exec_async(Command,Process,StreamToCmd,StreamFromCmd,ErrorsFromCmd) :-
	getRuntime(Runtime),
	exec(Runtime, Command, Process),
	getInputStream(Process, StreamFromCmdPipe),
	getErrorStream(Process, ErrorsFromCmdPipe),
	getOutputStream(Process, StreamToCmdPipe),
	open(StreamFromCmdPipe,read,StreamFromCmd,[stream]),
	open(ErrorsFromCmdPipe,read,ErrorsFromCmd,[stream]),
	open(StreamToCmdPipe,write,StreamToCmd,[stream]).