A memory leak with current df_3dmatrix routine

[Daniel J S. <dan...@ie...>]

Browsing through the df_3dmatrix() to make sure I've covered everything, 
I think I spotted a memory leak.  Near the top of the routine is

    if (df_binary) {
    if (!fread_matrix(data_fp, &dmatrix, &nr, &nc, &rt, &ct))
        int_error(NO_CARET, "Binary file read error: format unknown!");
    /* fread_matrix() drains the file */
    df_eof = 1;
    } else {

which records the memory pointers to vectors rt and ct and matrix 
dmatrix.  Then near the bottom of the routine is

    free_matrix(dmatrix, 0, nr - 1, 0);
    if (rt)
    free_vector(rt, 0);
    if (ct)
    free_vector(ct, 0);

But of course in between is all sorts of ways that the routine can error 
out.  Hence the memory leak.  Try

splot "binary1" binary using 1

a bunch of times and watch memory increase.

The way to fix this naturally is to make dmatrix, rt annd ct static and 
test for non-zero before allocating.  If non-zero, free before calling 
fread_matrix().  But again, whether it is worth fixing, I'm not sure. 
 (From my perspective, its obsolete.)

Dan