Redirect Output in the Middle of a Program??

[Larry Liuqing Huang]

Now more people are dialing into a system via telephone lines. It is
not unusual that the connection died out in the middle of a big C
program which you hate to start running from the beginning again.

Is it possible for the C program or Shell to detect the line problem?

If so, is it possible to redirect all standard output and error messages
to a designated file from the POINT where the problem is detected and 
continue running?

Any hints highly appreciated.

liuqing at cvl.umd.edu