gctl_get_intmax
val = gctl_get_intmax(req, "blocksize");
val = gctl_get_intmax(req, "size");
val = gctl_get_intmax(req, "iterations");
val = gctl_get_intmax(req, "keyno");
val = gctl_get_intmax(req, "iterations");
val = gctl_get_intmax(req, "keyno");
oldsize = gctl_get_intmax(req, "oldsize");
val = gctl_get_intmax(req, "mdversion");
val = gctl_get_intmax(req, "keylen");
val = gctl_get_intmax(req, "iterations");
val = gctl_get_intmax(req, "sectorsize");
val = gctl_get_intmax(r, "sectorsize");
jsize = gctl_get_intmax(req, "jsize");
val = gctl_get_intmax(req, "slice");
idx = (int)gctl_get_intmax(req, GPART_PARAM_INDEX);
idx = (int)gctl_get_intmax(req, GPART_PARAM_INDEX);
sectorsize = gctl_get_intmax(req, "sectorsize");
stripesize = gctl_get_intmax(req, "stripesize");
md.md_virsize = (off_t)gctl_get_intmax(req, "vir_size");
md.md_chunk_size = gctl_get_intmax(req, "chunk_size");
intmax_t gctl_get_intmax(struct gctl_req *req, const char *pfmt, ...) __printflike(2, 3);