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This file documents the mruby debugger ('mrdb') methods.
The trunk of the mruby source tree, with the most recent mrdb, can be checked out with the following command:
$ git clone https://github.com/mruby/mruby.git
To run the make command:
$ cd mruby $ make
By default, the make command will install the debugger files
into mruby/bin.
You can add the path for mrdb on your host environment with the following command:
$ echo "export PATH=\$PATH:MRUBY_ROOT/bin" >> ~/.bashrc $ source ~/.bashrc
*MRUBY_ROOT is the directory in which mruby source code will
be installed.
To confirm mrdb was installed properly, run mrdb with the
--version option:
$ mrdb --version mruby 2.0.1 (2019-4-4)
To invoke the mruby debugger, just type mrdb.
To specify the script file:
$ mrdb [option] file name
For example: Debugging sample.rb
$ mrdb sample.rb
You can execute the shell commands listed below:
|command|description| |:-:|:–| |run|execute programs| |step|execute stepping| |continue|execute continuing program| |break|configure the breaking point| |delete|deleting the breaking points| |disable|disabling the breaking points| |enable|enabling the breaking points| |info breakpoints|showing list of the breaking points| |print|evaluating and printing the values of the mruby expressions in the script| |list|displaying the source cords| |help|showing help| |quit|terminating the mruby debugger|
You can debug the mruby binary files.
notice To debug mruby binary files, you need to compile mruby files with
option -g.
$ mrbc -g sample.rb
You can debug the mruby binary files with following command and the option
-b.
$ mrdb -b sample.mrb
Then you can execute all debugger shell commands.
You can use any breakpoint to stop the program by specifying the line number and method name. The breakpoint list will be displayed after you have set the breakpoint successfully.
Usage:
break [file:]linenum b [file:]linenum break [class:]method b [class:]method
The breakpoint will be ordered in serial from 1. The number, which was given to the deleted breakpoint, will never be given to another breakpoint again.
You can give multiple breakpoints to specified the line number and method. Be ware that breakpoint command will not check the validity of the class name and method name.
You can get the current breakpoint information by the following options.
breakpoint breakpoint number : file name. line number
breakpoint breakpoint number : [class name,] method name
Usage:
continue [N] c [N]
N: the next breakpoint number
When resuming the program, it will stop at breakpoint N (N-1 breakpoint will be ignored).
When you run the continue command without specifying N, the
program will be stopped at the next breakpoint.
Example:
(foo.rb:1) continue 3
This will resume the program and stop it at the third breakpoint.
This will delete the specified breakpoint.
Usage:
delete [breakpoint-no] d [breakpoint-no]
breakpoint-no: breakpoint number
Example:
(foo.rb:1) delete
This will delete all of the breakpoints.
(foo.rb:1) delete 1 3
This will delete the breakpoint at 1 and 3.
This will disable the specified breakpoint.
Usage:
disable [breakpoint-no] dis [breakpoint-no]
reappointing: breakpoint number
Example:
(foo.rb:1) disable
Use disable if you would like to disable all of the
breakpoints.
(foo.rb:1) disable 1 3
This will disable the breakpoints at 1 and 3.
This will enable the specified breakpoints.
Usage:
enable [breakpoint-no] e [breakpoint-no]
breakpoint-no: breakpoint number
Example:
(foo.rb:1) enable
Enabling all breakpoints (foo.rb:1) enable 1 3
Enabling the breakpoint 1 and 3
Evaluating the string as source code and printing the value.
Same as print command, please see print command.
Displaying the help message.
Usage:
help [command] h [command]
Typing help without any options will display the command list.
Displaying the specified breakpoint information.
Usage:
info breakpoints [breakpoint-no] i b [breakpoint-no]
breakpoint-no: breakpoint number
Typing “info breakpoints” without ant option will display all breakpoint information. Example:
(sample.rb:1) info breakpoints Num Type Enb What 1 breakpoint y at sample.rb:3 -> file name,line number 2 breakpoint n in Sample_class:sample_class_method -> [class:]method name 3 breakpoint y in sample_global_method
Displaying the specified breakpoint number:
(foo.rb:1) info breakpoints 1 3 Num Type Enb What 1 breakpoint y at sample.rb:3 3 breakpoint y in sample_global_method
To display the code of the source file.
Usage:
list [filename:]first[,last] l [filename]:first[,last]
first: the opening row number last : the closing row number
When you specify the first, but not the last
option, you will receive 10 rows. When you do not specify both the
first and last options, you will receive the next
10 rows.
Example:
Specifying file name and first row number sample.rb:1) list sample2.rb:5
Specifying the file name and the first and last row number:
(sample.rb:1) list sample2.rb:6,7
Evaluating the string as source code and printing the value.
Usage:
print [expr] p [expr]
expr: expression
The expression is mandatory. The displayed expressions will be serially ordered from 1. If an exception occurs, the exception information will be displayed and the debugging will be continued.
Example:
(sample.rb:1) print 1+2 $1 = 3 (sample.rb:1) print self $2 = main
Below is the case of the exception:
(sample.rb:1) print (1+2 $1 = SyntaxError: line 1: syntax error, unexpected $end, expecting ')'
Quitting the debugger.
Usage:
quit q
Running the program and stopping at the first breakpoint.
Usage:
run r
This will run the program step by step. When the method and the block are invoked, the program will be stop at the first row. The program, which is developed in C, will be ignored.