detrunc
int detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred);
(void)detrunc(dep, dep->de_FileSize, 0, cred);
error = detrunc(dep, (u_long) 0, 0, NOCRED);
(void)detrunc(ddep, ddep->de_FileSize, 0, NOCRED);
error = detrunc(ip, (u_long)0, IO_SYNC, cnp->cn_cred);
error = detrunc(dep, vap->va_size, 0, cred);
detrunc(dep, osize, ioflag & IO_SYNC, NOCRED);
detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED);
(void) detrunc(dep, dep->de_FileSize, 0, cred);
(void)detrunc(ddep, ddep->de_FileSize, 0, NULL);