.\" Access Control Lists manual pages

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.\" (C) 2002 Andreas Gruenbacher, <a.gruenbacher@bestbits.at>

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.Dd March 23, 2002

.Dt ACL_CALC_MASK 3

.Os "Linux ACL"

.Sh NAME

.Nm acl_calc_mask

.Nd calculate the file group class mask

.Sh LIBRARY

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

.Sh SYNOPSIS

.In sys/types.h

.In sys/acl.h

.Ft int

.Fn acl_calc_mask "acl_t *acl_p"

.Sh DESCRIPTION

The

.Fn acl_calc_mask

function calculates and sets the permissions associated with the ACL_MASK

ACL entry of the ACL referred to by

.Va 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

.Va acl_p

already contains an ACL_MASK entry, its permissions are overwritten;

if it does not contain an ACL_MASK entry, one is added.

.Pp

If the ACL referred to by

.Va 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

.Va acl_p .

.Pp

The order of existing entries in the ACL is undefined after this function.

.Pp

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

.Va acl_p

continue to refer to the ACL.

.\" <AG>

.\" Conflict between requirements:

.\" (a) ACL may be relocated,

.\" (b) all pointers remain valid.

.\" </AG>

.Sh RETURN VALUE

.Rv -std acl_calc_mask

.Sh ERRORS

If any of the following conditions occur, the

.Fn acl_calc_mask

function returns

.Li -1

and sets

.Va errno

to the corresponding value:

.Bl -tag -width Er

.It Bq Er EINVAL

The argument

.Va acl

is not a valid pointer to an ACL.

.It Bq Er ENOMEM

The

.Fn acl_calc_mask

function is unable to allocate the memory required for an ACL_MASK ACL entry.

.El

.Sh STANDARDS

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

.Sh SEE ALSO

.Xr acl_check 3 ,

.Xr acl_get_entry 3 ,

.Xr acl_valid 3 ,

.Xr acl 5

.Sh 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 .