Question: The code that I'm analyzing calls fork and I was wondering if there was a way to trace the child process that is created. I've looked in *The IDAPro Book* and there's nothing on the topic (if there is I can't find it). Perhaps it's not possible with IDAPro. Also if it's helpful I'm debugging an elf executable remotely from a windows machine. Thanks in advance.

some basic documentation
<https://www.hex-rays.com/products/ida/support/idadoc/index.shtml>

Answer: 
This isn't IDA problem, per se. It's more to do with the debugger you're using. I assume you're using remote GDB through IDA. The debugger will attach itself to a specific process, and that process only. Fortunately, GDB has an option to follow child processes, using the debugging option:

`set follow-fork-mode child` 

Type that in the GDB prompt at the bottom of the Output Window in IDA, and the debugger should follow the path of execution of the forked child process. 

See [this page](http://sourceware.org/gdb/onlinedocs/gdb/Forks.html) for more info on debugging forks.
IDA does not support multi-process debugging at the moment (as of 2013). To debug the new process, you'll need to either detach from the current one, or use a new instance of IDA.