Moodle plugins directory: Virtual programming lab

Hi Juan,

Can I use this plugin, along with the jailserver, to run PHP assignments?

Thank you,
Horatiu

Yes, you can use VPL+jail server to run PHP assignments. VPL 3.1.X default script can run PHP5 CLI but not web programs. VPL 3.2 default script will run PHP to run web applications. But VPL is flexible anought to allow assigments of PHP web applications.
You can use and customize the default script of VPL3.2 for PHP and use it as vpl_run.sh

https://github.com/jcrodriguez-dis/moodle-mod_vpl/blob/v3.2/jail/default_scripts/php_run.sh

If you are using php7 remove php5 from line 10.

Best regards,
Juan Carlos.

Notice that you must reduce the security level of the firewall in the jail server service configuration to run PHP for a web application.

Happy new year!
You could add erlang to the list of languages available for VPL!

I've tried vpl for erlang: https://www.erlang.org/
=> that's ok (on my server and on the demo server): http://demovpl.dis.ulpgc.es/moodle/mod/vpl/view.php?id=399

It's just a small test.
1) I've changed the vpl_run.sh (for prolog) into:
. common_script.sh
check_program escript
cat common_script.sh > vpl_execution
echo "escript $VPL_SUBFILE0" >>vpl_execution
chmod +x vpl_execution

And
2) test with an erlang program:
-module(plusOne).
-compile(export_all).

plusOne(N)-> N+1.

main([]) ->
io:format('Give a number (end your line with .)~n',[]),
{ok,X} = io:read(':>'),
Y=plusOne(X),
io:format('~p + 1 => ~p ~n',[X,Y]).


That's all. And it works.

But I'm not a specialist with Erlang, and not a specialist with VPL. Maybe, there are better ways to do that.

Good surprise: the code editor colorized nicely erlang code (without anything to be done).

Best for you,
Denis B.

hi , when I submitted the c++ program to be compiled or evaluated. It shows the error message
"g++: error: unrecognized command line option ‘-fno-diagnostics-color’"
how can I fix it?

Best for you,
James TT

Hello Denis Bouhineau,
thank for your contribution. The next mayor release of VPL 3.3 will include a default script for Erlang.
Best regards.

Hello tt tt,
sorry for the inconvenience. You have two options:
1) Edit run_c.sh run_cpp.sh at mod/vpl/jail/default_scripts/ and remove that args. Also you can replace the C and C++ related scripts with the ones in the VPL 3.1.5
2) Upgrade your C++ compiler.

I will try to solve the problem in future releases.

Best regards,
Juan Carlos.

Hi Juan Carlos Rodríguez-del-Pino,
I am using the vpl module of moodle and i need to customize some of its functionalities.
I need to run sample testcases directly on RUN button and dont want command prompt to open and enter the input by user or student.
so any suggestions and idea u can give on this?

Hello ,
some one already use vpl to java code with package and two classes in the same package?
because, i test this example and i have error.
Thank for your help

Sorry Kushal Patel for the late answer.
If you want to avoid that the user interact when the students RUN their code you must modify the default script of the language you are using and redirect the standar input to /dev/null.
e.g. if you are using java you must get the java default script and copy it to your vpl_run.sh , then replace the line
echo "java -enableassertions $MAINCLASS" >> vpl_execution
by
echo "{" >> vpl_execution
echo "java -enableassertions $MAINCLASS" >> vpl_execution
echo "} < /dev/null" >> vpl_execution

I recomend to use the "based on" feature.

Best regards.

Hello Moussa Sarr,
you can use java classes and packages in VPL. To resolve the problem you need to give full detail of your code and how you use it in VPL.

Best regards.

Hi all,
I am able to run the following c program.
but I need to evaluate this program. please let us know if anyone can help me.
#include #include #include int main()
{

int pid, id;
if(fork() == 0)
{
/* open for writing */
printf("From child %d\n",getpid());
raise(2);
}

pid=wait(&id);
printf("From parent \n");
printf("Signal no= %d \n",id &355);

//waitpid(-1, NULL, 0);
return 0;

}

I don't know a easy way to test this type of program. I can imagine making a something similar to a facade pattern that replaces the API you are using to log and test the student's program behavior. But I also think it may be a hard and fragile way to test student's programs.
Best regards,
Juan Carlos.

Hi Juan,
Is there a support in VPL for Visual Basic?
Thank you,
Meir

Hi'

I'm not sure it's worth mentioning, I've modified locally the vpl_evaluate.cpp to cope with dot '.' in program output compared to expected output in vpl_evaluate.cases Else, punctuation ("Hi.") is confused with numbers (".5").
Here some explanation with a short example.
Suppose we want to test a program "+1" with the test.case :

Case = Test zero
input = 0
output = 1

Here a program solution (in C) :

int main() {
int n;
scanf("%d",&n);
printf("%d",n+1);
return 0;}

You can even give better solution :

int main() {
int n;
printf("Give a number ");
scanf("%d",&n);
printf("+1 : %d",n+1);
return 0;}

It works! VPL find the 0 and the 1 of the test.case. Great! It was not sure because of extra texts ("Give ..." and "+1 :"), but VPL skip these texts

But it does not work for :

int main() {
int n;
printf("Give a number.");
scanf("%d",&n);
printf("+1 : %d",n+1);
return 0;}

What's the difference? The difference is in the dot "." in the text "Give a number."! VPL think there is a number here...
The problem is in vpl_evaluate.cpp isNumStart

bool NumbersOutput::isNumStart(char c){
if(isdigit(c)) return true;
return c=='+' || c=='-' || c=='.';}

Yes, some numbers .5, .0, ... begin with a dot ".", but "." alone?
So I've changed it to :

bool NumbersOutput::isNumStart(char c){
if(isdigit(c)) return true;
return c=='-' ;}

And now, last program works. (but ".5" are to be written "0.5")

Best for you,
Denis B.

ps: There must be other solutions with better lexical analysis to recognize true numbers.