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From: keck@sea.com (John Keck)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Child processes in Mess-Dos
Message-ID: <1990Oct5.170852.29736@sea.com>
Date: 5 Oct 90 17:08:52 GMT
References: <619@demott.COM> <15651@yunexus.YorkU.CA> <4469@bwdls58.UUCP>
Organization: Systems Engineering Associates
Lines: 27

In article <4469@bwdls58.UUCP> mlord@bwdls58.bnr.ca (Mark Lord) writes:
>>>>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
>

Seems to me I read somewhere the EXE loader is part of COMMAND.COM.  So
perhaps the distinction is whether the child is COM or EXE file.

-- 
John Keck INTERNET:keck@sea.com UUCP:...!ucsd!soledad!keck VOICE:619/581-6181
Systems Engineering Associates, 2204 Garnet Ave Suite 203, San Diego CA 92109
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