acl_size(3) — Linux manual page


ACL_SIZE(3)             BSD Library Functions Manual             ACL_SIZE(3)

NAME         top

     acl_size — get the size of the external representation of an ACL

LIBRARY         top

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

SYNOPSIS         top

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

     acl_size(acl_t acl);

DESCRIPTION         top

     The acl_size() function return the size, in bytes, of the buffer
     required to hold the exportable, contiguous, persistent form of the ACL
     pointed to by the argument acl, when converted by acl_copy_ext().

     Any existing ACL entry descriptors that refer to entries in acl con‐
     tinue to refer to the same entries. Any existing ACL pointers that
     refer to the ACL referred to by acl continue to refer to the ACL. The
     order of ACL entries within acl remains unchanged.

RETURN VALUE         top

     On success, the acl_size() function returns the size in bytes of the
     contiguous, persistent form of the ACL. On error, a value of
     (ssize_t)-1 is returned and errno is set appropriately.

ERRORS         top

     If any of the following conditions occur, the acl_size() function
     returns a value of (ssize_t)-1 and sets errno to the corresponding

     [EINVAL]           The argument acl is not a valid pointer to an ACL.

STANDARDS         top

     IEEE Std 1003.1e draft 17 (“POSIX.1e”, abandoned)

SEE ALSO         top

     acl_copy_ext(3), acl(5)

AUTHOR         top

     Derived from the FreeBSD manual pages written by Robert N M Watson
     <>, and adapted for Linux by Andreas Gruenbacher

COLOPHON         top

     This page is part of the acl (manipulating access control lists)
     project.  Information about the project can be found at  If you have a bug report for
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     the date of the most recent commit that was found in the repository was
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Linux ACL                      March 23, 2002                      Linux ACL