how to run a program with gdb which is invoked from a shell script, which in turn invoked from c++ via boost::process

Question

I want to debug ac program with gdb which is invoked by shell script. In this shell script , there are lot of things done and many environment variables are set.

This shell script is invoked by boost::process::launch from a c++ program.

I can change c++ program, shell script, and the c program itself, but can't change the architecture of this flow.

Is there any way , so that i can use gdb to debug the program.

If there is no solution, is there a way to dump all environment settings before launching shell script, so that i can launch same script with these settings to debug it later. I will prefer a portable and long term solution.

Answer 1

Two easy options:

1. Attach gdb after the program has started with gdb -p <pid of process> if it doesn't matter to stop it at a specific point.

2. Insert a raise(SIGSTOP); in the C program where you want it to stop. Once the process is stopped, attach gdb as in 1 , set any breakpoints you need and then send the process a SIGCONT signal ( kill -CONT <pid of process> ) to cause it to continue.