Convert html string to pdf using wkhtmltopdf C library (wkhtmltox)

I am trying to convert html string to pdf using wkhtmltopdf C library. I checked the sample that comes together with the installer and I successfully compiled and converted the page. Here is the code that I used for reference.

wkhtmltopdf_global_settings * gs;
wkhtmltopdf_object_settings * os;
wkhtmltopdf_converter * c;

wkhtmltopdf_init(false);

gs = wkhtmltopdf_create_global_settings();

wkhtmltopdf_set_global_setting(gs, "out", "test.pdf");

os = wkhtmltopdf_create_object_settings();

wkhtmltopdf_set_object_setting(os, "page", "https://www.google.com.ph");

c = wkhtmltopdf_create_converter(gs);

wkhtmltopdf_set_progress_changed_callback(c, progress_changed);

wkhtmltopdf_set_phase_changed_callback(c, phase_changed);

wkhtmltopdf_set_error_callback(c, error);

wkhtmltopdf_set_warning_callback(c, warning);

wkhtmltopdf_add_object(c, os, NULL);

if (!wkhtmltopdf_convert(c))
    fprintf(stderr, "Convertion failed!");

printf("httpErrorCode: %d\n", wkhtmltopdf_http_error_code(c));

wkhtmltopdf_destroy_converter(c);

wkhtmltopdf_deinit();

I am suspecting that changing the parameters of the function

   wkhtmltopdf_set_object_setting(os, "page", "https://www.google.com.ph");

to something like

   wkhtmltopdf_set_object_setting(os, [name of setting], [html string]);

will do the job, however the documentation didn't specify any name for a particular setting aside from the one included in the sample which is "page".

Maybe I missed it in the documentation or maybe this is not the right way to do it. Any suggestion will be very much appreciated.

Solution

Thanks you for your time looking into this. I ended up with workaround. Instead of string i passed the local path of an generated html file. Its not the solution that I am looking for but it does the same thing. Thanks again.