tar_chksm
if (ul_oct(tar_chksm(hdblk, sizeof(HD_USTAR)), hd->chksum,
if (asc_ul(hd->chksum,sizeof(hd->chksum),OCT) != tar_chksm(blk,BLKMULT))
static u_long tar_chksm (char *, int);
if (ul_oct(tar_chksm(hdblk, sizeof(HD_TAR)), hd->chksum,
if (asc_ul(hd->chksum,sizeof(hd->chksum),OCT) != tar_chksm(blk,BLKMULT))