33.1  WHERE IS THE COMMAND LINE

DOS loads the command line into the PSP.  The length of the command line
is stored in a byte at offset 80h.  The command line is stored in the
next 127 bytes starting at 81h.  As, generally, there is a space between
the filename and the start of the command line argument; a space usually
is the first character in this string.  The string is terminated with a
carriage return character, 0dh.

At startup for both .COM and .EXE format programs, DS and ES point to
the PSP.

33.2  HOW TO ACCESS THE COMMAND LINE ARGUMENTS

See Subject #8, How to Redirect STDERR to a File.  I have written a
demonstration program that contains assembly language startup code that
parses the command line arguments onto the stack and provides them as
argc and *argv[] to the main procedure.  Anyone interested in accessing
command line arguments should look at this code.

Contributor:  Raymond Moon, raymoon@moonware.dgsys.com
Last changed: 15 Jun 96

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