Re: [wxperl-users] Wx::Perl::ProcessStream

[Eric W. <scr...@gm...>]

# from Mark Dootson
# on Monday 26 March 2007 09:03 pm:

>I'd appreciate any comments and views on code, process and namespace.

I would really like to see some sort of list-context (\@command or 
otherwise) functionality.  I've only briefly looked at the source, so 
there might be some underlying implementation nit forcing your hand 
here.

  my $process = Wx::Perl::ProcessStream->OpenProcess(
    $command, $name, $eventhandler);

With a quick glance around, it seems that Wx.pm supports the 
"wxExecute(char **argv,..." form via ExecuteArgs().  It also looks like 
this would be no different than using ExecuteCommand() in terms of 
firing the callback.  Perhaps detecting whether $command is an array 
ref would do it?

Of course, I'm assuming here that the list form in ExecuteArgs() carries 
all of the not-running-a-shell benefits of `exec(@list)` (such as "no 
need to escape spaces in filenames" to name one very common example.)  
If I'm wrong, ugh.  See also:  execvp(3).  The wx docs aren't exactly 
clear on what happens so ... at least the unix implementation 
("src/unix/utilsunx.cpp") reads as if they've reinvented shell 
escaping.  Neat.  So, maybe the semicolon ends up as an argument (I 
think perl goes out of its way to fire-up a shell.)  Ooh.  The windows 
implementation puts everything together and calls the string form due 
to the nature of CreateProcess.  Yay.  Well, I see from win32/win32.c 
create_command_line() that perl works a little harder.

In any case, I typically build command and arguments as lists.  Would 
rather not have to do join(" ", map({escape($_)} @list)) and then have 
wx go through that and split on spaces when the operating system is 
otherwise quite capable of executing a list of "command and arguments".  
I guess just leave "what should we do when the operating system is not 
so capable?" as an exercise for the reader.

--Eric
-- 
"Everything should be made as simple as possible, but no simpler."
--Albert Einstein
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