Way for examining executing code in a different obj file

[gsaxena@cs.kent.edu]

Dear folks at GDB,
I have the following program str:

[TXT] Makefile                05-Oct-2005 20:37  646
[TXT] common.h                05-Oct-2005 15:09  213
[TXT] control.cpp             30-Sep-2005 23:42  112
[TXT] control.h               03-Oct-2005 14:21  524
[IMG] image                   29-Sep-2005 20:03   48K
[TXT] init.c                  02-Oct-2005 02:39  4.6K
[TXT] init.h                  29-Sep-2005 20:03  784
[TXT] initfile                02-Oct-2005 02:33  554
[TXT] main.cxx                05-Oct-2005 20:38  5.2K
[   ] main                    05-Oct-2005 20:40  564K
[TXT] node.c                  05-Oct-2005 20:40  2.2K
[TXT] node.h                  03-Oct-2005 14:16  113
[   ] node                    05-Oct-2005 20:40  888K
[TXT] ppm.c                   29-Sep-2005 20:03  3.2K
[TXT] ppm.h                   29-Sep-2005 20:03  310
[DIR] public_html/            05-Oct-2005 18:40    -
[TXT] rand.cpp                02-Oct-2005 00:44  1.0K
[TXT] rand.h                  02-Oct-2005 00:46  122
[TXT] script

main.cxx is the main UserInterface code running libraries from fltk.
node.c is also compiled into an object called node. The node is using
libraries from lam-mpi for parallel operations. When I run the program in
gdb, I can see lines from main.cxx but occasionally the code in node.c is
also executed. I haven't understood how I can access the line nos. I'm not
even sure if it is possible. Could someone let me know what I must do ?

Thanks,
G