Problem using ruby_options() - help!

ruby-talk
1

Hello everyone,

I'm trying to call a Ruby program from C and pass it some arguments.
Here is a trivial program that demonstrates the problem. The Ruby
documentation states that you can set the Ruby arguments using
ruby_options. I know that if I pass no arguments it waits forever
listening to STDIN. Thats fine. The problem is that when I do pass
arguments Ruby just dies - no crash, nothing, just a silent exit.

Any idea what I'm doing wrong? Should I be using a different call to set
the arguments?

I'm using Ruby 1.8.1

int main(int argc, char* argv[])
{
        NtInitialize(&argc, &argv); // this bit need for Windows

        ruby_init();
        ruby_script("embedded");

        char *rubyArgs[] =
        {
                "arg1",
                "arg2",
                "arg3",
        };

        // this function should set the arguments to the ruby program
        // however Ruby silently dies at this point

        ruby_options(sizeof(rubyArgs) / sizeof(rubyArgs[0]), rubyArgs);

        // the code never gets here

        rb_load_file("e:\\doTheWork.rb");
        ruby_run();

        return 0;
}

Stephen

···

--
Stephen Kellett
Object Media Limited http://www.objmedia.demon.co.uk
RSI Information: http://www.objmedia.demon.co.uk/rsi.html

2

Quoteing snail@objmedia.demon.co.uk, on Wed, Dec 08, 2004 at 05:02:32AM +0900:

Hello everyone,

I'm trying to call a Ruby program from C and pass it some arguments.
Here is a trivial program that demonstrates the problem. The Ruby
documentation states that you can set the Ruby arguments using
ruby_options. I know that if I pass no arguments it waits forever
listening to STDIN. Thats fine. The problem is that when I do pass
arguments Ruby just dies - no crash, nothing, just a silent exit.

Any idea what I'm doing wrong? Should I be using a different call to set
the arguments?

I'm using Ruby 1.8.1

int main(int argc, char* argv)
{
        NtInitialize(&argc, &argv); // this bit need for Windows

        ruby_init();
        ruby_script("embedded");

I don't know anything about ruby here.. but I know the standard format
for ARGV arrays. perhaps you should null terminate rubyArgs?

        char *rubyArgs =
        {
                "arg1",
                "arg2",
                "arg3",

                  NULL

        };

        // this function should set the arguments to the ruby program
        // however Ruby silently dies at this point

ruby_options(sizeof(rubyArgs) / sizeof(rubyArgs[0]) - 1, rubyArgs);

Cheers,
Sam

···

        // the code never gets here

        rb_load_file("e:\\doTheWork.rb");
        ruby_run();

        return 0;
}

Stephen
--
Stephen Kellett
Object Media Limited http://www.objmedia.demon.co.uk
RSI Information: http://www.objmedia.demon.co.uk/rsi.html

3

Hi,

At Wed, 8 Dec 2004 05:02:32 +0900,
Stephen Kellett wrote in [ruby-talk:122839]:

I'm trying to call a Ruby program from C and pass it some arguments.
Here is a trivial program that demonstrates the problem. The Ruby
documentation states that you can set the Ruby arguments using
ruby_options. I know that if I pass no arguments it waits forever
listening to STDIN. Thats fine. The problem is that when I do pass
arguments Ruby just dies - no crash, nothing, just a silent exit.

What I got from your example (without NtIntialize) is:

  $ ./x
  arg1: No such file or directory -- arg2 (LoadError)

Any idea what I'm doing wrong? Should I be using a different call to set
the arguments?

I'm using Ruby 1.8.1

What's the exact version you are using, the result of `ruby -v'?

···

--
Nobu Nakada

4

listening to STDIN. Thats fine. The problem is that when I do pass
arguments Ruby just dies - no crash, nothing, just a silent exit.

I've got a solution.

I was originally making the following call which was dying.

        char *rubyArgs =
        {
                "arg1",
                "arg2",
                "arg3",
        };

        ruby_options(sizeof(rubyArgs) / sizeof(rubyArgs[0]), rubyArgs);

I built the ruby source and stepped through ruby_options() - it did
various strange things like calling ruby_script(args[0]) - thus
overwriting the value I'd already set, then later is message about with
args[1] and called ruby_script() on that messed about value, finally it
tried to load a file with the value of args[1]. That action failed and
ruby bailed out with an internal load error. Hence my problem.

Whilst doing the above I noticed the call ruby_set_argv(). A few tests
later and I conclude that the correct way to pass arguments to a Ruby
program, so far as I can tell is using

        ruby_set_argv(count, args);

Hope that helps someone, most likely using Google Groups to get
themselves out of this hole. Thanks to those that replied trying to help
me.

Stephen

···

--
Stephen Kellett
Object Media Limited http://www.objmedia.demon.co.uk
RSI Information: http://www.objmedia.demon.co.uk/rsi.html

5

Ruby 1.8.1 (2003-12-25) [i386-mswin32]

Stephen

···

In message <200412080520.iB85Ker4006311@sharui.nakada.niregi.kanuma.tochigi.jp>, nobu.nokada@softhome.net writes

I'm using Ruby 1.8.1

What's the exact version you are using, the result of `ruby -v'?

--
Stephen Kellett
Object Media Limited http://www.objmedia.demon.co.uk
RSI Information: http://www.objmedia.demon.co.uk/rsi.html

6

This was an interesting suggestion, but unfortunately doesn't fix the problem.

Stephen

···

In message <20041207215248.GB8458@ensemble.local>, Sam Roberts <sroberts@uniserve.com> writes

I don't know anything about ruby here.. but I know the standard format
for ARGV arrays. perhaps you should null terminate rubyArgs?

--
Stephen Kellett
Object Media Limited http://www.objmedia.demon.co.uk
RSI Information: http://www.objmedia.demon.co.uk/rsi.html

7

Hi,

At Thu, 9 Dec 2004 05:47:29 +0900,
Stephen Kellett wrote in [ruby-talk:122996]:

Whilst doing the above I noticed the call ruby_set_argv(). A few tests
later and I conclude that the correct way to pass arguments to a Ruby
program, so far as I can tell is using

        ruby_set_argv(count, args);

ruby_set_argv() sets the arguments for the script, while
ruby_options() accepts the arguments to the ruby interpreter,
including the script name and them.

···

--
Nobu Nakada