NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | STANDARDS | SEE ALSO | AUTHOR | COLOPHON

ACL_GET_QUALIFIER(3)    BSD Library Functions Manual    ACL_GET_QUALIFIER(3)

NAME         top

     acl_get_qualifier — retrieve the qualifier from an ACL entry

LIBRARY         top

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

SYNOPSIS         top

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

     void *
     acl_get_qualifier(acl_entry_t entry_d);

DESCRIPTION         top

     The acl_get_qualifier() function retrieves the qualifier from the ACL
     entry indicated by the argument entry_d into working storage and
     returns a pointer to that storage.

     If the value of the tag type in the ACL entry referred to by entry_d is
     ACL_USER, then the value returned by acl_get_qualifier() is a pointer
     to type uid_t.  If the value of the tag type in the ACL entry referred
     to by entry_d is ACL_GROUP, then the value returned by
     acl_get_qualifier() is a pointer to type gid_t.  If the tag type in the
     ACL entry referred to by entry_d is a tag type for which a qualifier is
     not supported, acl_get_qualifier() returns a value of (void *)NULL and
     the function fails. Subsequent operations using the returned pointer
     operate on an independent copy of the qualifier in working storage, and
     will not change the qualifier of the ACL entry.

     This function may cause memory to be allocated. The caller should free
     any releasable memory, when the new qualifier is no longer required, by
     calling acl_free() with the void * value returned by
     acl_get_qualifier() as an argument.

     The argument entry_d and any other ACL entry descriptors that refer to
     entries within the ACL containing the entry referred to by entry_d con‐
     tinue to refer to those entries. The order of all existing entries in
     the ACL containing the entry referred to by entry_d remains unchanged.

RETURN VALUE         top

     On success, the function returns a pointer to the tag qualifier that
     was retrieved into ACL working storage. On error, a value of (void
     *)NULL is returned and errno is set appropriately.

ERRORS         top

     If any of the following conditions occur, the acl_get_qualifier() func‐
     tion returns (void *)NULL and sets errno to the corresponding value:

     [EINVAL]           The argument entry_d is not a valid descriptor for
                        an ACL entry.

                        The value of the tag type in the ACL entry refer‐
                        enced by the argument entry_d is neither ACL_USER
                        nor ACL_GROUP.

     [ENOMEM]           The value to be returned requires more memory than
                        is allowed by the hardware or system-imposed memory
                        management constraints.

STANDARDS         top

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

SEE ALSO         top

     acl_create_entry(3), acl_free(3), acl_get_entry(3), acl_get_permset(3),
     acl_get_tag_type(3), acl_set_permset(3), acl_set_qualifier(3),
     acl_set_tag_type(3), acl(5)

AUTHOR         top

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

COLOPHON         top

     This page is part of the acl (manipulating access control lists)
     project.  Information about the project can be found at
     http://savannah.nongnu.org/projects/acl.  If you have a bug report for
     this manual page, see http://savannah.nongnu.org/bugs/?group=acl.  This
     page was obtained from the project's upstream Git repository
     git://git.savannah.nongnu.org/acl.git on 2017-09-15.  If you discover
     any rendering problems in this HTML version of the page, or you believe
     there is a better or more up-to-date source for the page, or you have
     corrections or improvements to the information in this COLOPHON (which
     is not part of the original manual page), send a mail to
     man-pages@man7.org

Linux ACL                      March 23, 2002                      Linux ACL