fortran_fcgi.f90

! Adapted from https://github.com/mapmeld/fortran-machine

program fortran_lambda

    use fcgi_protocol

    implicit none

    type(DICT_STRUCT), pointer  :: dict => null() ! Initialisation is important!
    logical                     :: stopped = .false. ! set to true in respond() to terminate program
    integer                     :: unitNo ! unit number  for a scratch file

    ! open scratch file
    open(newunit=unitNo, status='scratch')
    ! comment previous line AND uncomment next line for debugging;
    !open(newunit=unitNo, file='fcgiout', status='unknown') ! file 'fcgiout' will show %REMARKS%

    ! wait for environment variables from webserver
    do while (fcgip_accept_environment_variables() >= 0)

        ! build dictionary from GET or POST data, environment variables
        call fcgip_make_dictionary( dict, unitNo )

        ! give dictionary to the user supplied routine
        ! routine writes the response to unitNo
        ! routine sets stopped to true to terminate program
        call respond(dict, unitNo, stopped)

        ! copy file unitNo to the webserver
        call fcgip_put_file( unitNo, 'text/html' )

        ! terminate?
        if (stopped) exit

    end do !  while (fcgip_accept_environment_variables() >= 0)

    ! before termination, it is good practice to close files that are open
    close(unitNo)

    ! webserver will return an error since this process will now terminate
    unitNo = fcgip_accept_environment_variables()


contains
    subroutine respond ( dict, unitNo, stopped )

        type(DICT_STRUCT), pointer        :: dict
        integer, intent(in)               :: unitNo
        logical, intent(out)              :: stopped

        ! start of response
        write(unitNo, AFORMAT) &
            	'Hello, World!'

        return

    end subroutine respond

end program fortran_lambda