statacl or fstatacl Subroutine

Purpose

Retrieves the AIXC ACL type access control information for a file.

Library

Standard C Library (libc.a)

Syntax

#include <sys/acl.h>
#include <sys/stat.h>

int statacl (Path, Command, ACL, ACLSize)
char * Path;
int  Command;
struct acl * ACL;
int  ACLSize;

int fstatacl (FileDescriptor, Command, ACL, ACLSize)
int  FileDescriptor;
int Command;
struct acl *ACL;
int ACLSize;

Description

The statacl and fstatacl subroutines return the access control information for a file system object if the ACL associated is of AIXC type. If the ACL associated is of different type or if the underlying physical file system does not support AIXC ACL type, error could be returned by these interfaces. If the statacl subroutine is used on NFS V4 files, invalid results are returned.

Parameters

Item Description
Path Specifies a pointer to the path name of a file.
FileDescriptor Specifies the file descriptor of an open file.
Command Specifies the mode of the path interpretation for Path, specifically whether to retrieve information about a symbolic link or mount point. Valid values for the Command parameter are defined in the stat.h file and include:
  • STX_LINK
  • STX_MOUNT
  • STX_NORMAL
ACL Specifies a pointer to a buffer to contain the AIXC-type Access Control List (ACL) of the file system object. The format of an AIXC ACL is defined in the sys/acl.h file and includes the following members:
acl_len
Size of the Access Control List (ACL).
Note: The entire ACL for a file cannot exceed one memory page (4096 bytes).
acl_mode
File mode.
Note: The valid values for the acl_mode are defined in the sys/mode.h file.
u_access
Access permissions for the file owner.
g_access
Access permissions for the file group.
o_access
Access permissions for default class others.
acl_ext[ ]
An array of the extended entries for this access control list.

The members for the base ACL (owner, group, and others) may contain the following bits, which are defined in the sys/access.h file:

R_ACC
Allows read permission.
W_ACC
Allows write permission.
X_ACC
Allows execute or search permission.
ACLSize Specifies the size of the buffer to contain the ACL. If this value is too small, the first word of the ACL is set to the size of the buffer needed.

Return Values

On successful completion, the statacl and fstatacl subroutines return a value of 0. Otherwise, a value of -1 is returned and the errno global variable is set to indicate the error.

Error Codes

The statacl subroutine fails if one or more of the following are true:

Item Description
ENOTDIR A component of the Path prefix is not a directory.
ENOENT A component of the Path does not exist or has the disallow truncation attribute (see the ulimit subroutine).
ENOENT The Path parameter was null.
EACCES Search permission is denied on a component of the Path prefix.
EFAULT The Path parameter points to a location outside of the allocated address space of the process.
ESTALE The process' root or current directory is located in a virtual file system that has been unmounted.
ELOOP Too many symbolic links were encountered in translating the Path parameter.
ENOENT A symbolic link was named, but the file to which it refers does not exist.
ENAMETOOLONG A component of the Path parameter exceeded 255 characters, or the entire Path parameter exceeded 1023 characters.

The fstatacl subroutine fails if the following is true:

Item Description
EBADF The file descriptor FileDescriptor is not valid.

The statacl or fstatacl subroutine fails if one or more of the following are true:

Item Description
EFAULT The ACL parameter points to a location outside of the allocated address space of the process.
EINVAL The Command parameter is not a value of STX_LINK, STX_MOUNT, STX_NORMAL.
ENOSPC The ACLSize parameter indicates the buffer at ACL is too small to hold the Access Control List. In this case, the first word of the buffer is set to the size of the buffer required.
EIO An I/O error occurred during the operation.

If Network File System (NFS) is installed on your system, the statacl and fstatacl subroutines can also fail if the following is true:

Item Description
ETIMEDOUT The connection timed out.