doug@wiley.uucp (Doug Rudoff) (06/16/90)
I am having a very hard time with a program that uses shared memory. Basically, when I try to copy something out of shared memory, all I get are zeroes. By copy I mean using either an assignment (like x=ptr->except), a memcpy(), and even evaluations like "if (!ptr->exception)". If I run the program in a debugger (I've used dbx and gdb with the same result) and looked at the shared memory, all the right data is there. But all the copies, assignments and evaluations act as if there's only zero's in the memory. EXCEPT (this is the weird part) when I step through the program one line at a time, all the data from shared memory is copied properly! (When the program is run without the debugger it doesn't work). The other process using the shared memory uses it with no problem. I've tried various kludges to get around this, assigning other pointers into shared memory, and writing the portion of shared memory I'm interested in into a file. All I get are zeroes. Does anyone have any ideas about what is going on here? (I'm using a DECstation 3100 with Ultrix 3.1) Doug Rudoff Mobile Data International Bothell, WA (206) 487-5937 rudoff@mdi.com uunet!mdisea!rudoff (Note that this is not the machine I post from)