Path: utzoo!utgpu!cunews!bnrgate!bwdls58!mlord
From: mlord@bwdls58.bnr.ca (Mark Lord)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Child processes in Mess-Dos
Message-ID: <4469@bwdls58.UUCP>
Date: 1 Oct 90 21:32:43 GMT
References: <1990Sep28.234836.17868@gpu.utcs.utoronto.ca> <619@demott.COM> <15651@yunexus.YorkU.CA>
Sender: mlord@bwdls58.UUCP
Reply-To: mlord@bwdls58.bnr.ca (Mark Lord)
Organization: Bell-Northern Research, Ottawa, Canada
Lines: 23

>>>Others were under the impression that spawn and exec load an additional
>>>copy of COMMAND.COM.  I didn't test to see if this is true, but I doubt it.
>
>>    If you doubt it, make your comspec=a:\command.com and see how slowly
>>your program comes up.  I've just gone through that exercise.
>
>I've done one better: I wrote a little program that spawned a memory
>mapper as its child.  The resulting map clearly shows that there is
>*no* copy of command.com loaded by spawn().

Ok.. I believe the difference here is whether or not the complete path is
given for the command.  If fully qualified, COMMAND.COM is not needed,
otherwise it probably is needed to do the PATH search and actual invocation.

Ie.  "C:\BIN\MAPMEM.COM"  -- probably does not need COMMAND.COM
     "MAPMEM"             -- probably DOES need COMMAND.COM

I say probably because my Machine is unavailable to verify this theory for now.
-- 
 ___Mark S. Lord__________________________________________
| ..uunet!bnrgate!mlord%bmerh724 | Climb Free Or Die (NH) |
| MLORD@BNR.CA   Ottawa, Ontario | Personal views only.   |
|________________________________|________________________|