C++ Pass a string into a pipe to gnuplot -

i'm having small problem passing string gnuplot c++ can pass integers enough, when try string (user defined "title" earlier in code):

fprintf(gnuplotpipe, "set title %s\n", title);

i error:

error: cannot pass objects of non-trivially-copyable type ‘std::string {aka class std::basic_string<char>}’ through ‘...’

so instead tried using:

fprintf(gnuplotpipe, "set title %s\n", title.c_str());

and code compiled, when ran got error gnuplot:

line 0: undefined variable: h

where "h" test sting defined "title".

does have ideas on how pass this?

thanks in advance!

you have put title in quotes:

fprintf(gnuplotpipe, "set title \"%s\"\n", title.c_str());

Th