CVBUG.TXT                        Jan 24, 1987

This document contains a description of a CodeView bug/feature involving
argv[0].

C programs compiled with Microsoft C Version 4.0 and executed under
PC/MS DOS 3.0 or greater place a path-file_name pointer in argv[0] .
The path-file_name string can be used to determine a path to the
where the program resides (as oppossed to the currently selected
directory).  Remember this only works with DOS 3.0 or greater.

For example, a program called "timecek.exe" which resides in directory
C:\TEST\C\ would be envolked by setting a path to \TEST\C\ and typing 
"timecek". Argv[0] would point to the string containing
C:\TEST\C\TIMECEK.EXE . Note , the string is all caps and the program
name extension (.EXE) has been appended.

Using CodeView to debug the above program, you would normally be "logged"
to the C:\TEST\C directory and enter "cv timecek" . Displaying the string
pointed to by argv[0] results in "timecek.exe".  Note, no path, program
name in lower case. 

If you are using argv[0] to determine the "home" directory  you are lost.
ACTUALLY, CodeView sets argv[0] to point to WHATEVER you enter as a
filename.For example,

	Command Line			*argv[0]

	cv TiMeCeK			TiMeCeK.exe
	cv c:\test\c\timecek		c:\test\c\timecek.exe
	cv C:\TEST\C\TIMECEK		C:\TEST\C\TIMECEK.exe

If you ignore the string case, you can "fake" CodeView to supply
the same string that will be available when you run your program.

I am not sure if MicrSoft intended such operation, but at least
it is a bug/feature which can be "defeated" if desired .

                        Dave Campbell
                        Compuserve [74116,3324]