Hi,

I've a subroutine that's written in C. My main program and everything else are in fortran 90. I have a global data module which consist of some variables and it can be assessed globally ie

module global_data

implicit none

save

real :: dd(10)

end module global_data

I would like to pass the values of a variable (e.g. dd) to a C subroutine, do some calculation, and out comes the result of the variable.

How can I do this? Is there a sample code somewhere? I tried to find some info on the net but they seem quite complicated...

Btw, my environment is visual studio and linux.

Thanks in advance!

Look in your compiler manual to find out how to mix C and Fortran subroutines. This varies from compiler to compiler. In simple cases it involves little more than knowing the naming convention for Fortran subroutines (common examples are fred_ or fred__) and declaring the C function to be an external C function in Fortran so that the name does not get underscores attached when linking.