C_NOTRUNC
{ "notrunc", C_NOTRUNC, 0, NULL },
if (!(ddflags & (C_SEEK | C_NOTRUNC)))
if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK) &&
if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) == C_BS) {