general Informations and Key shortcuts for Kent Sibilev's great ruby-debug gem.
http://www.datanoise.com/ruby-debug/, http://rubyforge.org/projects/ruby-debug/
A reference manual for version 0.10.0 is at http://bashdb.sf.net/ruby-debug.html
Installation
gem install ruby-debug
Usage
rdebug [options] <script.rb> -- <script.rb parameters>
startup settings:
rdebug reads its configuration file at startup.
create a file ~/.rdebugrc with this content:
set autolist
set autoeval
set autoreload
after starting rdebug like: rdebug script/server
enter 'c' and 'return' for starting up rdebug finally.
Most important commands:
r[eload], n[ext], c[ont]
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Commands (available as 'help <command-name>' in active debug mode)
backtrace (alias for where)
(rdb:1) bt|backtrace
break
(rdb:1) b[reak] file:line [if expr]
(rdb:1) b[reak] class(.|#)method [if expr]
set breakpoint to some position, (optionally) if expr == true
Before version 0.10.0:
(rdb:1) b[reak] list breakpoints
0.10.0 or later:
(rdb:1) info b[reak]
catch
(rdb:1) cat[ch] (show catchpoint)
(rdb:1) cat[ch] <an Exception> (set catchpoint to an exception)
cont
(rdb:1) c[ont][ nnn] (run until program ends or hits breakpoint or reaches line
nnn)
delete
(rdb:1) del[ete][ nnn] (delete some or all breakpoints)
disable
(rdb:1) disable BPT-NUM - disable given breakpoint number
display
(rdb:1) disp[lay] <expression> (add expression into display expression list)
(rdb:1) disp[lay] (display expression list)
down
(rdb:1) down[count] (move to lower frame)
enable
(rdb:1) enable BPT-NUM - enable given breakpoint number
eval
(rdb:1) e[val] expression evaluate expression and print its value, alias for p.
* NOTE - to turn on autoeval, use 'set autoeval'
exit
(rdb:1) q[uit] exit from debugger,
(rdb:1) exit alias to quit
finish
(rdb:1) fin[ish] return to outer frame
frame
(rdb:1) f[rame] frame-number
Move the current frame to the specified frame number.
A negative number indicates position from the other end.
So 'frame -1' moves to the oldest frame, and 'frame 0' moves to
the newest frame.
help
(rdb:1) h[elp] print help
(rdb:1) h[elp] command print help on command
irb
(rdb:1) irb starts an IRB session. (EXPERIMENTAL)
list
(rdb:1) l[ist] list forward
(rdb:1) l[ist] - list backward
(rdb:1) l[ist] = list current line
(rdb:1) l[ist] nn-mm list given lines
method
(rdb:1) m[ethod] i[nstance] <obj> show methods of object
(rdb:1) m[ethod] <class|module> show instance methods of class or module
next
(rdb:1) n[ext][+][ nnn] step over once or nnn times,
'+' forces to move to another line
p
p(rdb:1) expression evaluate expression and print its value
pp
(rdb:1) pp expression evaluate expression and pretty-print its value
quit
(rdb:1) q[uit] exit from debugger,
(rdb:1) exit alias to quit
reload
(rdb:1) r[eload] forces source code reloading
restart
(rdb:1) restart|R [args]
Restart the program. This is is a re-exec - all debugger state
is lost. If command arguments are passed those are used.
save
(rdb:1) save FILE saves current breakpoints and catchpoint as a script
file
Before 0.10.0:
(rdb:1) script FILE executes a script file
After 0.10.0 (to be gdb compatible):
(rdb:1) source FILE executes a script file
set
(rdb:1) set <setting>
where <setting>:
args - argument list to give program being debugged when restarted
autolist - execute 'list' command on every breakpoint
autoeval - evaluate every unrecognized command
autoreload - enables automatic source code reloading
autoirb - debugger invokes IRB on every stop
listsize - number of source lines to list by default
trace - display stack trace when 'eval' raises exception
framefullpath - frame will display full file names
frameclassname - frame will display class names
forcestep - make sure 'next/step' commands always move to a new line
width - number of characters the debugger things are in aline
To disable setting, use 'no' prefix, like 'noautolist' or "off" as in
"autolist off"
step
(rdb:1) s[tep][ nnn] step (into methods) once or nnn times
thread
(rdb:1) th[read] l[ist] list all threads
(rdb:1) th[read] [sw[itch]] <nnn> switch thread context to nnn
(rdb:1) th[read] stop <nnn> stop thread nnn
(rdb:1) th[read] c[ur[rent]] show current thread
(rdb:1) th[read] resume <nnn> resume thread nnn
trace
(rdb:1) tr[ace] (on|off) set trace mode of current thread
(rdb:1) tr[ace] (on|off) all set trace mode of all threads
undisplay
(rdb:1) undisp[lay][ nnn] delete one particular or all display expressions
up
(rdb:1) up[count] move to higher frame
var
(rdb:1) v[ar] const <object> show constants of object
(rdb:1) v[ar] g[lobal] show global variables
(rdb:1) v[ar] i[nstance] <object> show instance variables of object
(rdb:1) v[ar] l[ocal] show local variables
Before 10.0 const can be abbreviated "c", after 10.0 or later you need
"co" because there is also "var class".
where
(rdb:1) w[here] display frames
