Programming

      {"interp-p",      required_argument, 0,  6},
       {"varp",      required_argument, 0,  7},
     {"ifbase",  required_argument, 0,  8},
     {"iftdat",  required_argument, 0,  9},
     {"ifmodl",  required_argument, 0,  10},
      {"ifpopl",  required_argument, 0,  11},
      {"ofmodl",  required_argument, 0,  12},
      {"ofpopl",  required_argument, 0,  13},
      {"ofexpl",  required_argument, 0,  14},
      {"nlayers", required_argument, 0,  15},
      {"ni",      required_argument, 0,  16},
      {"nxp",     required_argument, 0,  17},
      {"nzp",     required_argument, 0,  18},
      {"nxs",     optional_argument, 0,  19},
      {"nzs",     optional_argument, 0,  20},
      {"ngenr",   optional_argument, 0,  21},
      {"nmodl",   optional_argument, 0,  22},
      {"objv",    optional_argument, 0,  23},
      {"genitor", optional_argument, 0,  24},
      {"chrmrep", optional_argument, 0,  25},
      {"elitsel", optional_argument, 0,  27},
      {"msel",    optional_argument, 0,  26},
      {"mcrs",    optional_argument, 0,  28},
      {"rsel",    required_argument, 0,  29},
      {"rcrs",    optional_argument, 0,  30},
      {"rmut",    optional_argument, 0,  31},
      {"hdwvs",   optional_argument, 0,  32},
      {"tstep",   optional_argument, 0,  33},
      {"intgm",   optional_argument, 0,  34},
      {"dangl",   optional_argument, 0,  35},
      {"textr",   optional_argument, 0,  36},
      {"sigma",   optional_argument, 0,  37},
      {"colour",        no_argument, 0,  33},
      {"lglvl",   optional_argument, 0,  34},
      {"brief",         no_argument, 0, 'b'},
      {"detailed",      no_argument, 0, 'd'},
      {"examples",      no_argument, 0, 'e'},
      {"help",          no_argument, 0, 'h'},

Tomog  T;

--ifbase
--iftdat
--nxp
--nzp
--varp
--interp-p

class myclass
{
public:
        // options::x was set by config::parse(), called by main().
        // We can use it directly, no need to pass anything anywhere.
        myclass() { x = options::x; }
        int x;
};

int main(int argc, char *argv[])
{
       options::parse(argc, argv);
       myclass something;
}

// These lines should only be in one file, but the functions
// and variables they instantiate can be used globally.
int options::x=-1, options::y=-1, options::z=-1;

bool options::parse(int argc, char *argv[])
{
        x=5;
        y=6;
        z=7;
}

// These lines should only be in one file, but the functions
// and variables they instantiate can be used globally.
int options::x=-1, options::y=-1, options::z=-1;

bool options::parse(int argc, char *argv[])
{
        x = argv[0];
        y = argv[1];
        z = argv[2];
}

option::parse