Note: Before you start the debugger, make sure that you have correctly set the size information for your terminal; otherwise, the debugger's command line editing support may act unpredictably. For example, if your terminal is 25x80, you may need to set the following:
% stty rows 25 ; setenv LINES 25
% stty cols 80 ; setenv COLS 80
There are four basic alternatives for running the debugger on a process (see examples below):
Intel IDB starts operating in DBX mode by default, so you do not have to specify any special options in the shell command line.
Examples:
1. Creating the process using the shell command line.
% idb a.out
Intel(R) Debugger for ..., Version ..., Build ...
------------------
object file name: a.out
Reading symbolic information ...done
(idb) stop in main
[#1: stop in int main(void) ]
(idb) run
2. Creating the process using the debugger commands.
% idb
Intel(R) Debugger for ..., Version ..., Build ...
------------------
(idb) load a.out
Reading symbolic information ...done
(idb) stop in main
[#1: stop in int main(void) ]
(idb) run
3. Attaching to a running process using the shell command line.
% ./a.out &
[1] 27859
% jobs
[1]+ Running ./a.out &
% idb a.out -pid 27859
Intel(R) Debugger for ..., Version ..., Build ...
------------------
Reading symbolic information ...done
Attached to process id 27859 ....
Press Ctrl+C to interrupt the process.
4. Attaching to the process using the debugger commands.
% ./a.out &
[1] 27859
% jobs
[1]+ Running ./a.out &
% idb
Intel(R) Debugger for ..., Version ..., Build ...
------------------
(idb) attach 27859 a.out
Reading symbolic information ...done
Attached to process id 27859 ....
Press Ctrl+C to interrupt the process.
To start the debugger in the GDB mode, specify the -gdb option in the shell command line.
Examples:
1. Creating the process using the shell command line.
% idb -gdb a.out
Intel(R) Debugger for ..., Version ..., Build ...
------------------
object file name: a.out
Reading symbols from a.out...done
(idb) break main
Breakpoint 1 at 0x80484f6: file qwerty.c, line 9.
(idb) run
2. Creating the process using the debugger commands.
% idb -gdb
Intel(R) Debugger for ..., Version ..., Build ...
-------------------
(idb) file a.out
Reading symbols from a.out...done.
(idb) break main
Breakpoint 1 at 0x80484f6: file qwerty.c, line 9.
(idb) run
3. Attaching to a running process using the shell command line.
% ./a.out &
[1] 27859
% jobs
[1]+ Running ./a.out &
% idb -gdb a.out -pid 27859
Intel(R) Debugger for ..., Version ..., Build ...
------------------
object file name: a.out
Reading symbols from a.out...done.
Attached to process id 27859 ....
Press Ctrl+C to interrupt the process.
4. Attaching to the process using the debugger commands.
% ./a.out &
[1] 27859
% jobs
[1]+ Running ./a.out &
% idb -gdb
Intel(R) Debugger for ..., Version ..., Build ...
(idb) file a.out
Reading symbols from a.out...done.
(idb) attach 27859
Attached to process id 27859 ....
Press Ctrl+C to interrupt the process.
Note: In the case of Fortran, routine main at which your program stops is not your main program unit. Rather, it is a main routine supplied by the Fortran system that performs some initialization and then calls your code. Just step forward using the step command a couple of times (probably twice) and you will soon step into your code.
Note: If you want full compatibility with GDB output, you need to set the debugger variable $gdb_compatible_output to 1. Otherwise, IDB will produce the extended GDB output in some cases.
See Attaching to a Running Program for the information about how to obtain the PID of a program.