rdebug(1)rdebug(1)NAMErdebug - Fast Ruby debugger
SYNOPSISrdebug [debugger-options] rdebug [script-options...]
DESCRIPTION
This manual page documents briefly the rdebug command.
rdebug is a fast implementation of the standard Ruby debugger debug.rb.
It is implemented by utilizing a Ruby C API hook, allows for remote
debugging and can be used as the Ruby debugger backend interface for a
development environment.
The commands generally follow gdb's command set unless there's good
reason not to.
rdebug can do four main kinds of things (plus other things in support
of these) to help you catch bugs in the act:
· Start or restart your Ruby script, specifying arguments that
might affect its behavior.
· Make your program stop at various points possibly determined by
specified conditions.
· Examine what has happened when your program has stopped.
· Change things in your program, so you can experiment with cor‐
recting the effects of one bug and go on to learn about another.
Here are some of the most frequently-needed commands:
break [file:line|class.method] [if expr]
Set a breakpoint at class.method or at the specified file and
line.
continue [line]
Continue running your program (after stopping, e.g. at a break‐
point). If a line is given a one-time breakpoint is set there.
delete [breakpoint-numbers]
Delete breakpoints by number. If no number is given delete all
breakpoints.
down [count]
Move down one block frame. If count is given move up that many
frames. A negative number goes the other direction and is like
the up command
finish Run until the completion of the current function or method.
frame frame-number
Set the stack frame to frame-number for purposes of examinine
local variables. For positioning relative to the current frame,
use up or down. A negative number starts counting from the other
end.
help [name]
Show information about rdebug command name, or general informa‐
tion about using rdebug.
info [name]
Get the various information usually about the debugged program.
irb command
Run an interactive ruby shell (irb) using the current environ‐
ment.
list [file:line|function]
type the text of the program in the vicinity of where it is
presently stopped or at the specified function or file and line.
next [count]
Execute next program line(s) (after stopping); step over any
function calls in the line.
pp expr
Pretty print the value of an expression.
print expr
Display the value of an expression.
ps expr
Print an array as a columized sorted list.
quit Exit from the debugger.
run [arglist]
(Re)start your program (with arglist, if specified). If you want
the debugger to get reloaded, use restart instead.
set Modify parts of the debugger environment.
show See the debugger environment settings
source filename
Read and execute the lines in file filename as a series of
debugger commands.
step [count]
Execute next program line(s) (after stopping); step into any
function calls in the line.
up [count]
Move up one block frame. If count is given move up that many
frames. A negative number goes the other direction and is like
the down command
where [count]
Display all or count items of the program stack.
For full details on rdebug, see https://github.com/cldwalker/debugger
OPTIONS-A | --annotate LEVEL
Set gdb-style annotation to LEVEL, a number. Addi‐
tional information is output automatically when pro‐
gram state is changed. This can be used by front-ends
such as GNU Emacs to post this updated information
without having to poll for it.
--client Connect to a remote debugger. Used with another rdebug
invocation using --server. See also --host and
--cport options
--cport=PORT
Port used for control commands.
-d | --debug
Set $DEBUG true.
--emacs Activates full GNU Emacs mode. Is the equivalent of
setting the options --emacs-basic, --annotate=3, --no-
stop, --no-control and --post-mortem.
--emacs-basic
Activates GNU Emacs mode. Debugger prompts are pref‐
aced with two octal 032 characters.
-h | --host=HOST
Host name used for remote debugging.
-I | --include PATH
Add PATH to $LOAD_PATH
-m | --post-mortem
Activate post-mortem mode.
--no-control
Do not automatically start control thread.
--no-stop Do not stop when script is loaded.
-p | --port=PORT
Host name used for remote debugging.
-r | --require SCRIPT
Require the library, before executing your script.
--script FILE
Name of the script file to run.
-x | --trace
Show lines before executing them.
--no-quit Do not quit when script terminates. Instead rerun the
program.
--version Show the version number and exit.
--verbose Turn on verbose mode.
--v Print the version number, then turn on verbose mode if
a script name is given. If no script name is given
just exit after printing the version number.
--nx Don't execute commands found in any initialization
files, e.g. .rdebugrc.
--keep-frame-binding
Keep frame bindings.
--script=FILE
Name of the script file to run -s | --server Listen
for remote connections. Another rdebug session
accesses using the --client option. See also the
--host, --port and --cport options
-w | --wait
Wait for a client connection, implies -s option.
--help Show invocation help and exit.
SEE ALSO
https://github.com/cldwalker/debugger
AUTHORrdebug was written by Kent Siblev. This manual page was written
by Rocky Bernstein <rocky@gnu.org>
rdebug(1)
