Bug 435727

Description of problem:

I am trying to perform remote debugging using eclipse and gdb.
I run eclipse on a FC8 linux computer with the latest updates 
(one host system is an acer travelmate; the other an and desktop;
the problem does not depend on the host platform).

The client system is a powerpc 405 set-top box running a minimal 
busybox=based version of linux. With gdb and ddd I could debug an application
on this system by specifying 
ddd --debugger 'ssh -t client.telin /tmp/command'
were /tmp/command contains a command line that starts the program to
debug under gdb.

I now follow a similar approach to debug the client system from 
eclipse and it basically works very well, except for one showstopper:
When I select "suspend" from the menu, the program is not suspended,
but gdb exists. In information scattered around the internet, I have 
seen related reports, but never exactly equal.

To simplify testing of the problem, I switched to debugging the following
helloworld.c program, which is debugged (using ssh to simulate 
remote debugging) and run on the same system.

int main(void) {
	printf("Hello World!!!");
	sleep(100);
	printf("hello done");
	return 0;
}



Relevant settings are:

eclipse:
---------
-connect process input_output to a terminal
-gdb debugger: /home/philips/workspace/hello/hellodebug
-gdb command set: stanadard linux (also tried other settings)
-protocol mi (tried various combinations)
-verbose console mode
-Allocate console (necessary for input)

hellodebug
------------
!/bin/bash
ssh -t eltodo.telin /home/philips/workspace/hello/hellodebug1
#bash -c /home/philips/workspace/hello/hellodebug1

hellodebug1
------------
#!/bin/bash
cd /home/philips/workspace/hello; 
gdb  -q -nw -i mi  --cd=/home/philips/workspace/hello --command=.gdbinit
/home/philips/workspace/hello/hello



It is not 100% clear if gdb is at fault or eclipse, but I am sure 
that the problem is related to the communication between both, as the
testcases below illustrate. Also, based on the test cases, 
I think it is more likely that eclipse is at fault rather than gdb.


I hope that this issue can be resolved. I am willing to do 
some more experiments.


Version-Release number of selected component (if applicable):

#rpm -q eclipse-cdt gdb
eclipse-cdt-4.0.1-3.fc8
gdb-6.6-43.fc8


How reproducible:
Always

Steps to Reproduce:
1. start eclipse. 

2. Run debug with the above settings. Step twice with F6 
until sleep line activates. 

3. Use "suspend" in the debug menu. 

Actual results:

gdb exits. See console.ssh.log

Expected results:
gdb should not exit, allowing me to debug the program


Additional info:

With a slightly modified hellodebug script **all works as expected**
(see console.bash.log; which ends just after I select "suspend" from the menu):
-eclipse displays a stack trace. Thread 0 has a message next to
it "suspended: signal 'SIGINT' receved'"). 
-I can continue to run the program.

The only modification is that I replace "ssh -t  eltodo.telin" with
"bash -c". Of course this is totally useless for remote debugging but it 
illustrates that the problem is in the communication between eclipse 
and the (remote) gdb.


As another experiment, I ran hellodebug (ssh version) from the commandline
(see commandline.log).
I started hellodebug and then typed
b main
run
n
n
control-c

All worked as expected.


In conclusion: when eclipse is not involved, all works as expected.
Otherwise, I have problems.


Note: I do not want to use gdbserver because the settop box
application I am debugging is multithreaded and gdbserver is too 
limited for that.