The gdb debugger is available for use with
programs compiled with the g++ compiler. It is used
to locate run-time errors. The C++ program must be
compiled with the -g flag in order to use the
debugger.
unix level commands -- entered after the bgunix $
prompt:
| help |
to display a list of gdb commands |
| help command |
to get help on a specified gdb command |
| run |
to run/execute the program starting from the
beginning |
| continue |
to resume running/executing the program |
| next |
to execute the current statement and stop at
the next statement |
| step |
same as next, but step into a function |
| list xx |
list source lines starting at line
xx |
| list |
to list the next source lines |
| list xx,yy |
to list sources lines from line xx
to line yy |
| list filename:xx |
to list source lines in the specified file
starting at line xx |
| quit |
to quit gdb and revert to the unix command
level |
| break functionname |
to set a breakpoint at the start of a
function |
| break
classname::functionname |
to set a breakpoint at the start of a member
function |
| break filename:xx |
to set a breakpoint at line xx in
the specified file |
| break xx |
to set a breakpoint at line xx in
the current file |
| break 1 |
to set a breakpoint at the first line in the
current file (declaration or executable
statement) |
| info break |
to list all breakpoints (including those
disabled); breakpoints are numbered #1, #2, #3,
etc. |
| disable xx |
to disable breakpoint #xx |
| enable xx |
to enable breakpoint #xx |
| print v1 |
to print the value of a specified
variable |
| info source |
to show the name of the current source
file |
| info sources |
to list the name of all source files in
use |
| set variable = value |
to assign a new value to a specified
variable |
| (return) |
to re-execute the previous gdb command; this
is particularly useful if the previous gdb
command was next or step |
You can also execute most gdb commands by entering
only the first letter of the command.
