Path: utzoo!attcan!uunet!lll-winken!ames!mailrus!iuvax!purdue!decwrl!labrea!polya!ali
From: ali@polya.Stanford.EDU (Ali T. Ozer)
Newsgroups: comp.sys.next
Subject: Re: extra terminal launch
Message-ID: <6075@polya.Stanford.EDU>
Date: 13 Jan 89 15:02:18 GMT
References: <1478@mace.cc.purdue.edu>
Reply-To: aozer@NeXT.com (Ali Ozer)
Organization: .
Lines: 41

In article <1478@mace.cc.purdue.edu> abe@mace.cc.purdue.edu (Vic Abell) writes:
>When I double-click from the browser to launch an application I have built
>with the Interface Builder (e. g., the Celsius to Fahrenheit calculator), it
>is always accompanied by the automatic launch of an extra terminal process,
>complete with window and menu, followed by the requested application's
>displays.  Does anyone know why this happens?

When the Workspace is launching an app, if it doesn't recognize the app
as a Mach executable, it assumes the app cannot be run directly. So
a Terminal is started and the app is run in the Terminal. (Or at least
that's what it seems like. Amiga users will recognize this as the
same kind of thing that happens when XIcon or IconX is used to 
automatically start a shell to run programs that cannot be directly
run from the Workbench.)

By default, the IB generated Makefile lacks the few lines of magic
that makes an executable into a Mach executable. Take a look at some of
the makefiles in /MyDisk/Programming/Examples/*. Some have LFLAGS
(or LDFLAGS; these are the command line options that get passed to the
linker) are set to something that looks like:

LFLAGS = -g -segcreate __ICON __tiff foo.tiff __ICON __header foo.header

(This is from memory; so please double check.)
The "-g" is debug; the rest of the flags specify the creation of a
Mach segment called "__ICON" which holds icon-image information for
this program. "foo.tiff" and "foo.header" are two files which contain
information about the icons; you can, if you wish, simply replace those 
two files by an zero-length file. This way you get a Mach segment,
preventing the Terminal window from appearing during launchtime.
(But you won't have a custom icon for your app.) You can automate
the creation of a such a zero-length file with a "touch" appropriately
placed in the Makefile; some examples do this, I believe.

This stuff isn't very well documented, even in the official Tech Docs
for 0.8, mainly because it's all going to be automated or somehow
made easier in the future. Workspace behaviour might also be changed for 
non-Mach executables.

Ali Ozer, NeXT Developer Support
aozer@NeXT.com