acl_calc_mask(3) — Linux manual page
ACL_CALC_MASK(3) Library Functions Manual ACL_CALC_MASK(3)
NAME
acl_calc_mask — calculate the file group class mask
LIBRARY
Linux Access Control Lists library (libacl, -lacl).
SYNOPSIS
<sys/types.h> <sys/acl.h> int acl_calc_mask(acl_t *acl_p)
DESCRIPTION
The acl_calc_mask() function calculates and sets the permissions
associated with the ACL_MASK ACL entry of the ACL referred to by
acl_p. The value of the new permissions is the union of the
permissions granted by all entries of tag type ACL_GROUP,
ACL_GROUP_OBJ, or ACL_USER. If the ACL referred to by acl_p
already contains an ACL_MASK entry, its permissions are
overwritten; if it does not contain an ACL_MASK entry, one is
added.
If the ACL referred to by acl_p does not contain enough space for
the new ACL entry, then additional working storage may be
allocated. If the working storage cannot be increased in the
current location, then it may be relocated and the previous
working storage is released and a pointer to the new working
storage is returned via acl_p.
The order of existing entries in the ACL is undefined after this
function.
Any existing ACL entry descriptors that refer to entries in the
ACL continue to refer to those entries. Any existing ACL pointers
that refer to the ACL referred to by acl_p continue to refer to
the ACL.
RETURN VALUE
The acl_calc_mask() function returns the value 0 if successful;
otherwise the value -1 is returned and the global variable errno
is set to indicate the error.
ERRORS
If any of the following conditions occur, the acl_calc_mask()
function returns -1 and sets errno to the corresponding value:
[EINVAL] The argument acl is not a valid pointer to an
ACL.
[ENOMEM] The acl_calc_mask() function is unable to
allocate the memory required for an ACL_MASK
ACL entry.
STANDARDS
IEEE Std 1003.1e draft 17 (“POSIX.1e”, abandoned)
SEE ALSO
acl_check(3), acl_get_entry(3), acl_valid(3), acl(5)
AUTHOR
Derived from the FreeBSD manual pages written by Robert N M
Watson <rwatson@FreeBSD.org>, and adapted for Linux by Andreas
Gruenbacher <andreas.gruenbacher@gmail.com>.
COLOPHON
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 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-04-25.) If you discover any rendering
problems in this HTML version of the page, or you believe there
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(which is not part of the original manual page), send a mail to
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