[MACTCL] [Q] C extensions and passing lists....

[Michael N. \(mnorton\) <mn...@ci...>]

Hi,

From inside my C extension code, what is the correct way to access a
list that is passed in as an argument?=20
My objective with this operation is to learn about writing C extensions.
I know vector libraries exist and so
forth.=20

Thanks,

Mike

Here is my code.

static int
 mmatrix_Cmd(
     ClientData cdata,
     Tcl_Interp *interp,
     int objc,
     Tcl_Obj * CONST objv[])
 {
     /* set the matrix pointer */
     char *mptr;
     for (mptr =3D objv[1]; *mptr !=3D '\0'; mptr++)
     {
        printf("mmatrix_Cmd (%s)\n", mptr);
     }

     Tcl_SetObjResult(interp, Tcl_NewStringObj("mmatrix_Cmd done", -1));
     return TCL_OK;
 }=20

Is the list passed in using objv?

Here is what I am passing in from Tcl.

load ~/script_dev/skunk_works/C_ext/vector
=20

  # Eq 3.3 Rx, Real-Time Rendering, Moller & Haines
  #  note t - theta
  #
  #         |  cos t   0   sin t   0  |
  # Ry(t) =3D |   0      1    0      0  |
  #         | -sin t   0   cos t   0  |
  #         |   0      0    0      1  |
  #
  set Ry { \
              {0 0 0 0} \
              {0 1 0 0} \
              {0 0 0 0} \
              {0 0 0 1} \
          }
=20

puts $Ry
=20

mmatrix $Ry