Help to checkpoint and rollback processes

[Robert Side]

I have a problem I hope somebody can help me with.

Long Summary:
I would like to be able to *checkpoint* a running process
so that the process, which is under user control, can be rollbacked to a
given checkpoint and restarted.

My idea to solve the problem:
The way I have been thinking to solve the problem is to save
the process's data, stack and registers when a checkpoint
occurs and when the user rollbacks the process, the saved
data, stack, and registers are copied into the process's memory
image and hopefully the process will think it is back at the time
the checkpointed was taken.

Cravats:
Sun-3 workstations running Sun UNIX 4.2 Release 3.3. There will
be open files as well as open sockets. The ptrace system call can
be used.

What I need help with:
I would like to know if the problem can be solved,
what literature (if any) has been written on the above problem,
what problems will arise, and, MOST OF ALL, how to do it.

Please email responses (But I do read these groups) and I will
summarize.

*MANY* thanks in advance and any help will be greatly appreciated.

Rob Side

Robert Side <rside at uvunix.uvic.cdn>
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Robert Side <rside at uvunix.uvic.cdn>
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