acl_get_file man page
acl_get_file — get an ACL by filename
Linux Access Control Lists library (libacl, -lacl).
acl_get_file(const char *path_p, acl_type_t type);
The acl_get_file() function retrieves the access ACL associated with a file or directory, or the default ACL associated with a directory. The pathname for the file or directory is pointed to by the argument path_p. The ACL is placed into working storage and acl_get_file() returns a pointer to that storage.
In order to read an ACL from an object, a process must have read access to the object's attributes.
The value of the argument type is used to indicate whether the access ACL or the default ACL associated with path_p is returned. If type is ACL_TYPE_ACCESS, the access ACL of path_p is returned. If type is ACL_TYPE_DEFAULT, the default ACL of path_p is returned. If type is ACL_TYPE_DEFAULT and no default ACL is associated with the directory path_p, then an ACL containing zero ACL entries is returned. If type specifies a type of ACL that cannot be associated with path_p, then the function fails.
This function may cause memory to be allocated. The caller should free any releasable memory, when the new ACL is no longer required, by calling acl_free(3) with the (void*)acl_t returned by acl_get_file() as an argument.
On success, this function returns a pointer to the working storage. On error, a value of
(acl_t)NULL is returned, and errno is set appropriately.
If any of the following conditions occur, the acl_get_file() function returns a value of
(acl_t)NULL and sets errno to the corresponding value:
Search permission is denied for a component of the path prefix or the object exists and the process does not have appropriate access rights.
Argument type specifies a type of ACL that cannot be associated with path_p.
The argument type is not ACL_TYPE_ACCESS or ACL_TYPE_DEFAULT.
The length of the argument path_p is too long.
The named object does not exist or the argument path_p points to an empty string.
The ACL working storage requires more memory than is allowed by the hardware or system-imposed memory management constraints.
A component of the path prefix is not a directory.
The file system on which the file identified by path_p is located does not support ACLs, or ACLs are disabled.
IEEE Std 1003.1e draft 17 (“POSIX.1e”, abandoned)
acl_free(3), acl_get_entry(3), acl_get_fd(3), acl_set_file(3), acl(5)
Derived from the FreeBSD manual pages written by Robert N M Watson ⟨rwatson@FreeBSD.org⟩, and adapted for Linux by Andreas Gruenbacher ⟨email@example.com⟩.
acl(5), acl_delete_def_file(3), acl_extended_file(3), acl_free(3), acl_from_mode(3), acl_get_entry(3), acl_get_fd(3), acl_init(3), acl_set_fd(3), acl_set_file(3), explain(1), explain(3), explain_acl_get_file(3), explain_acl_get_file_or_die(3).