nstrlen
t1 = s1 + nstrlen(s1, bptr) - 1;
t2 = s2 + nstrlen(s2, bptr) - 1;
t2 = s2 + nstrlen(s2, bptr) - 1;
ptr1 += nstrlen(PS_END_GLOBAL, bptr);
trailer->size = nstrlen(trailer->start,
document->size = nstrlen(document->start,