Hey everyone, I found how to generate a coredump on OSX!
http://osxbook.com/book/bonus/chapter8/core/
There is a downloadable program there, in source form. I downloaded it, compiled it, and, hooray! It worked! It generated an almost 1GB core dump!
Whether or not the information is in there doesn't quite matter now. I learnt how to generate coredumps on OSX, which is definitely could be a handy skill as a software developer ;) You never know when a core dump could come in handy.
I can just imagine a few years time I'm doing an important job, and I need a core dump to figure out whats going on, and this "gcore" app is what I needed. Even if it pays off once... this is a good thing.
In your simplified example, you have two processes (your shell, and the cat) trying to read from the “slave” side of the tty. The result is that one process gets some of the characters, the other gets the others.
What do you mean by “redirect the input from one [terminal] to the other”? In your real situation, what processes are trying to read from each terminal? What do you want to do with your captured input once you have it? What, exactly, are you actually trying to accomplish?
To me, “redirect the io of a process running in gdb” seems more like re-opening stdin/stdout/stderr inside a process that is already running.
You can change stdin/stdout/stderr of a running process with (among other things) GDB. An answer to “Redirect STDERR / STDOUT of a process AFTER it’s been started, using command line?” shows how it can be done. You would want to substitute a tty pathname for /dev/null
in the answer, and you probably want to handle stdin, too, but the technique is still applicable.
You should be able to make your simplified example work robustly, but I am not convinced that it does what you actually want to do (keep in mind that a pseudo terminal is actually a pair of devices, like two ends of a bidirectional pipe; but all your example does it interact with the ‘slave’ halves).
The key to fixing your example is to get all but one of the competing process to (temporarily) stop read from the terminal. If, like your example, you have a shell running on the side from which you would like to capture data, then you can do something like this:
(
s="$(stty -g)"
exec 3<&0
trap 'stty "$s" 0<&3;exit' 0 INT QUIT
cat <<EOM
In some other terminal, run the command
cat <$(tty)
Press ^C or ^\ to quit.
EOM
stty raw isig brkint susp '' dsusp ''
while true; do sleep 3600; done </dev/null
)
Best Answer
Use powershell rather than the typical cmd prompt. Just type powershell to open up a term. Then in powershell type Get-Process to list all processes. To get a specific process do Get-Process -Id 99. Of course 99 would be your PID.