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ACL_GET_FILE

Section: C Library Functions (3)
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BSD mandoc
Linux ACL

NAME

acl_get_file - get an ACL by filename

LIBRARY

Linux Access Control Lists library (libacl, -lacl).

SYNOPSIS

In sys/types.h In sys/acl.h Ft acl_t Fn acl_get_file const char *path_p acl_type_t type

DESCRIPTION

The Fn 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 Fn 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_free3 with the (void*)acl_t returned by Fn acl_get_file as an argument.

RETURN VALUE

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.

ERRORS

If any of the following conditions occur, the Fn acl_get_file function returns a value of (acl_t)NULL and sets errno to the corresponding value:

Bq Er EACCES: 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
Bq Er EINVAL: The argument type is not ACL_TYPE_ACCESS or ACL_TYPE_DEFAULT.
Bq Er ENAMETOOLONG: The length of the argument path_p is too long.
Bq Er ENOENT: The named object does not exist or the argument path_p points to an empty string.
Bq Er ENOMEM: The ACL working storage requires more memory than is allowed by the hardware or system-imposed memory management constraints.
Bq Er ENOTDIR: A component of the path prefix is not a directory.
Bq Er ENOTSUP: The file system on which the file identified by path_p is located does not support ACLs, or ACLs are disabled.

STANDARDS

IEEE Std 1003.1e draft 17 (lqPOSIX.1erq, abandoned)

AUTHOR

Derived from the FreeBSD manual pages written by An Robert N M Watson Aq rwatson@FreeBSD.org , and adapted for Linux by An Andreas Gruenbacher Aq a.gruenbacher@bestbits.at .