SYSCTL_DDB_CAPTURE_DATA
if (sysctlbyname(SYSCTL_DDB_CAPTURE_DATA, NULL, &buflen, NULL, 0) < 0)
err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_DATA);
ret = sysctlbyname(SYSCTL_DDB_CAPTURE_DATA, buffer, &len, NULL, 0);
err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_DATA);