[comp.sys.mac] "system" call

sl@van-bc.UUCP (Stuart Lynne) (04/24/87)

I need a call similiar to the unix "system" to put into a uucp 
program to do the uuxqt part.

Has anyone out there in netland gotten around to implementing
a method of calling another program with proper return to the
calling program when finished? For example similiar to the 
unix "system" call. 

Do any of the Mac C compilers have this type of a routine. I'm
using Aztec, and have check MPW, neither seem to have it.

Aztec does have exec in various forms, but really just gives you
chaining. 


-- 
Stuart Lynne	ihnp4!alberta!ubc-vision!van-bc!sl     Vancouver,BC,604-937-7532

jww@sdcsvax.UCSD.EDU (Joel West) (04/26/87)

In article <663@van-bc.UUCP>, sl@van-bc.UUCP (Stuart Lynne) writes:
> I need a call similiar to the unix "system" to put into a uucp 
> program to do the uuxqt part.

the way to do this is to:
	1. Find out who's the current 'Finder' and save the name
	2. Make your program the current finder.
	3. _Chain to the program.
	4. Wait to come back.

I've not done it myself, so I don't know whether you want _Launch
or _Chain (i.e., when you come back, your heap might not be
re-initialized if you try _Chain, but I'm not sure).

This is what the MPW shell does when you run an application, and
it looked like what the Aztec shell does, too.
-- 
	Joel West
	{ucbvax,ihnp4}!sdcsvax!jww	(ihnp4!gould9!joel once I fix news)
	jww@sdcsvax.ucsd.edu	if you must

mark@hyper.UUCP (04/27/87)

in article <663@van-bc.UUCP>, sl@van-bc.UUCP (Stuart Lynne) says:
> Posted: Fri Apr 24 03:17:39 1987
> 
> Has anyone out there in netland gotten around to implementing
> a method of calling another program with proper return to the
> calling program when finished? For example similiar to the 
> unix "system" call. 

Switcher provides this kind of capability. LightSpeed C uses it to run your
program in a private partition and then return to LSC instantly.  Get a hold
on a copy of "Inside Switcher".
-- 
Mark G. Mendel, ihnp4!umn-cs!hyper!mark,  Network Systems Corporation

All opinions expressed herein, even the most arbitrary, are defended by my 
employer with religious fervor.

tomas@apple.UUCP (04/27/87)

In article <3042@sdcsvax.UCSD.EDU> jww@sdcsvax.UCSD.EDU (Joel West) writes:
>In article <663@van-bc.UUCP>, sl@van-bc.UUCP (Stuart Lynne) writes:
>> I need a call similiar to the unix "system" to put into a uucp 
>> program to do the uuxqt part.
>
>the way to do this is to:
>	1. Find out who's the current 'Finder' and save the name
>	2. Make your program the current finder.
>	3. _Chain to the program.
>	4. Wait to come back.
>
>I've not done it myself, so I don't know whether you want _Launch
>or _Chain (i.e., when you come back, your heap might not be
>re-initialized if you try _Chain, but I'm not sure).
>
>This is what the MPW shell does when you run an application, and
>it looked like what the Aztec shell does, too.
>-- 
>	Joel West
>	{ucbvax,ihnp4}!sdcsvax!jww	(ihnp4!gould9!joel once I fix news)
>	jww@sdcsvax.ucsd.edu	if you must

This is NOT the way the MPW Shell does it.

Tom Taylor / Development Systems Group

lsr@apple.UUCP (04/27/87)

In article <3042@sdcsvax.UCSD.EDU> jww@sdcsvax.UCSD.EDU (Joel West) writes:
>In article <663@van-bc.UUCP>, sl@van-bc.UUCP (Stuart Lynne) writes:
>> I need a call similiar to the unix "system" to put into a uucp 
>> program to do the uuxqt part.
>
>the way to do this is to:
>	1. Find out who's the current 'Finder' and save the name
>	2. Make your program the current finder.
>	3. _Chain to the program.
>	4. Wait to come back.

I have good news and bad news.  

The good news is that there is a much easier way to do this.  The more
recent systems support a sublaunch protocol, which allows one program to
launch another and regain control when the other program finishes.  It does
not require changing low memory globals.  There is an extended set of
parameters to the Launch call that indicates is a sublaunch is desired.

The bad news?  You will have to wait a couple of weeks to get the full
details. 

The reason is that this feature is going to be documented in the next set
of Tech Notes, which are due to be distributed in a couple of weeks.  I am
one of the Tech Note reviewers, which is why I know about this.
Unfortunately, I returned my review copy, so I don't have the exact details
around.  (Plus, I would prefer to wait for the official Tech Note release,
just in case the review copy had errors.)

I will post the information as soon as I get it.  (Although given the way
Tech Notes are distributed, people outside Apple will probably see them
first.) 

-- 
Larry Rosenstein

Object Specialist
Apple Computer

AppleLink: Rosenstein1
UUCP:  {sun, voder, nsc, mtxinu, dual}!apple!lsr
CSNET: lsr@Apple.CSNET