if (plist == NULL)
errx(1, "missing -f flag");
for (int i = 0; required_flags[i].flag != NULL; i++)
for (unsigned int i = 0; required_flags[i].flag != NULL; i++)
if (pkg_get(pkg, required_flags[i].attr) == NULL)
errx(1, "missing %s flag", required_flags[i].flag);