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getgroups

Implemented in Antinomie 0.7.0 · Syscall list

long getgroups(int gidsetsize, gid_t *grouplist);
Number (x86-64) 115
ABI common
Kernel entry point sys_getgroups

This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.

Reads the caller’s supplementary group ids into an array.

Name Type Meaning
gidsetsize (arg0) int Number of group ids the buffer holds.
grouplist (arg1) gid_t * Pointer to an array of group ids.

On success: the number of supplementary groups.

In an Antinomie trace the Return column and the ret filter field show the raw kernel return value. On failure that is the negative errno, for example -2 for ENOENT, not the -1 plus errno that the libc wrapper gives. syscall.errno holds the positive errno and syscall.success is false.

Raw return Name Meaning
-14 EFAULT A pointer argument points outside the accessible address space.
-22 EINVAL An argument is invalid.

getgroups(2) on man7.org

Coverage mark: Implemented. Every pointer argument has a capture rule in the pinned kernel patch and none of them records a “no decoder”, “address only” or “not observed” gap on any code path. Individual values can still be incomplete on a particular call; see the capture statuses.

Every call is recorded as an Entry record (the six argument words and the pointees copied at entry) and an Exit record (the return value and the pointees copied at exit).

Argument When How Recorded field key Condition
gidsetsize (arg0) Entry raw scalar word args.0, args.gidsetsize
grouplist (arg1) Entry the pointer itself, as a raw word args.1, args.raw[1]
↳ pointee Exit array of 4-byte group ids, count min(gidsetsize (arg0), result), limit 65,536 entries arg1.data result is 0 or greater
  • Result: ret, syscall.errno, syscall.success, syscall.duration_ns.
  • Argument words: args.gidsetsize (arg0), args.grouplist (arg1); args.0 to args.5 by position.

See Syscall Trace filter for the full syntax.

For what the capture statuses mean, see Capture statuses. For what is never recorded, see Known gaps.