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setxattr

Implemented in Antinomie 0.7.0 · Syscall list

long setxattr(const char *path, const char *name, const void *value, size_t size, int flags);
Number (x86-64) 188
ABI common
Kernel entry point sys_setxattr

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

Sets an extended attribute of the file at a path, following symbolic links.

Name Type Meaning
path (arg0) const char * Path, as a NUL-terminated string in user memory.
name (arg1) const char * Name string (a path, queue name, module name or attribute name depending on the call).
value (arg2) const void * Value to set or compare.
size (arg3) size_t Size in bytes.
flags (arg4) int Option flags that change the behavior of the call.

On success: 0.

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
-61 ENODATA The requested data or attribute does not exist.
-95 ENOTSUP The operation is not supported (same value as EOPNOTSUPP).
-1 EPERM The operation is not permitted for this process.

setxattr(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
path (arg0) Entry the pointer itself, as a raw word args.0, args.raw[0]
↳ pointee Entry NUL-terminated string, up to 4,096 bytes (PATH_MAX) arg0.path always
name (arg1) Entry the pointer itself, as a raw word args.1, args.raw[1]
↳ pointee Entry NUL-terminated attribute name, up to 256 bytes arg1.xattr_name always
value (arg2) Entry the pointer itself, as a raw word args.2, args.raw[2]
↳ pointee Entry attribute value; length size (arg3); “invalid extent” above 64 KiB arg2.xattr_data always
size (arg3) Entry raw scalar word args.3, args.size
flags (arg4) Entry raw scalar word; Syscall Trace also decodes it into flag names (xattr group), listing unknown bits separately args.4, args.flags
  • Result: ret, syscall.errno, syscall.success, syscall.duration_ns.
  • Argument words: args.path (arg0), args.name (arg1), args.value (arg2), args.size (arg3), args.flags (arg4); args.0 to args.5 by position.
  • Captured strings: the args.<name> field of a path argument, and args.path, give the captured text instead of the pointer.

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.