ref: cde4b93a27af60da423b3ed387de5f7a31ba32b7
dir: /sys/src/cmd/ext4srv/group.h/
typedef struct Group Group; typedef struct Groups Groups; struct Group { u32int id; char *name; Group *memb; int nmemb; }; struct Groups { char *raw; Group *g; int ng; }; int loadgroups(Groups *gs, char *raw); void freegroups(Groups *gs); Group *findgroup(Groups *gs, char *name, u32int *id); Group *findgroupid(Groups *gs, u32int id); int ingroup(Group *g, u32int id);