xfopenat
if ((fp = xfopenat(savedirfd, "bounds", O_RDONLY, "r")) == NULL) {
if ((fp = xfopenat(savedirfd, "bounds", O_WRONLY | O_CREAT | O_TRUNC,
if ((info = xfopenat(savedirfd, infoname,
if ((fp = xfopenat(savedirfd, "minfree", O_RDONLY, "r")) == NULL)