/*  0123456789 123456789 123456789 123456789 123456*/
  char *z = mprintf("Content-Disposition: attachment; filename=\"%s\";\r\n",
                    zFilename);
  int i;
  int n = (int)strlen(z);
  for(i=43; i<n-4; i++){
    char c = z[i];
    if( isalnum(c) ) continue;
    if( fossil_isalnum(c) ) continue;
    if( c=='.' || c=='-' || c=='/' ) continue;
    z[i] = '_';
  }
  cgi_append_header(z);
  fossil_free(z);
}