Program runs under sdb, but when called direct?!?!

[Dr. Megabyte]

I have a program, the recent VC spreadsheet program on my 
AT&T 3b2/400 with SVR2.  I compiled it without errors.  When I
try to run it, the program does nothing, so I treid to use
the sdb debugger on it.  When I used "sdb vc" and then issued
the "r" command to run the program, it ran fine!!
 
What could make a program run perfectly under the debugger, but
not from the shell?
-- 
UUCP:	(1) seismo!why_not!scsnet!sunder		Mark E. Sunderlin
	(2) ihnp4!chinet!megabyte			aka Dr. Megabyte
CIS:	74026,3235					(202) 634-2529
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