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kbdcomp(1M)

kbdset(1)

alp(7)



kbdload(1M)                    DG/UX 5.4R3.00                    kbdload(1M)


NAME
       kbdload - load or link att_kbd tables

SYNOPSIS
       kbdload [-p] filename
       kbdload -u table
       kbdload -l string
       kbdload -L string
       kbdload -e string

DESCRIPTION
       Tables included in the file filename are loaded into the attkbd
       STREAMS module, which must already have been pushed into the standard
       input STREAM.  (In this context loaded means copied from a disk file
       into main memory within the operating system.)  This program is
       intended both to provide for loading and linking of both shared or
       public tables and private tables implementing user-specific
       functionality.  New users should refer to kbdcomp(1M) and attkbd(7)
       for a general description of the module's capabilities.

       Files are searched for only by the name given on the command line; no
       search path is implied.  Tables loaded by the superuser with the -p
       option from an absolute path beginning at /usr/lib/kbd are made
       publicly available and permanently resident, otherwise the loaded
       tables are available only to the caller, and are automatically
       unloaded when the attkbd module is popped from the STREAM.

       The -u option can be used to unload private tables and by the
       superuser to remove public tables.  Tables may be unloaded only if
       they are not currently in use.  (Tables which are members of
       composite tables always have non-zero reference counts since they are
       ``used'' in the composite; all composites which refer to them must be
       unloaded first.)

       The -L and -l options are used for making composite tables on-the-
       fly.  The -L option, if executed by the superuser, causes the
       composite to be made publicly available; it is otherwise private and
       -L is equivalent to -l.  The string argument is constructed in the
       same manner as the link statement [see kbdcomp(1M)] in the compiler.
       If any component of the intended composite is not presently loaded in
       memory or if a component of a public table is not also public, an
       error message is printed and the linkage fails.  More than one
       composite may be created in a single invocation by using either
       option sequentially.

       The -e option with a string argument causes kbdload to declare to the
       attkbd module a subroutine called string, which is assumed to be a
       subroutine managed by and registered with the alp module [see
       alp(7)].  These ``external'' subroutines may be used exactly as any
       other loaded table; they may participate as members of composite
       tables, etc.

   Security Issues
       Allowing users other than the superuser to load public tables is a



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kbdload(1M)                    DG/UX 5.4R3.00                    kbdload(1M)


       security risk and is thus disallowed.  (In general, any manipulation
       of a module instance by a user who is neither the superuser nor the
       user who originally pushed it is disallowed.)  The library directory
       and all files contained in it should be protected by being
       unwritable.  Administrators are encouraged to remember that the
       attkbd system can be used to arbitrarily re-map the entire keyboard
       of a terminal, as well as the entire output STREAM; thus in extremely
       hostile environments, it might be prudent to remove execution
       permissions from kbdload for non-administrative users (for example,
       setting the owner to bin or root and giving it a mode of 0500).

       The kbdload command checks to insure that the real-uid of the invoker
       is the same as the owner of both standard input and standard output
       files, unless the real-uid of the invoking user is the superuser.
       Paths to public tables are scrutinized for legitimacy.  The kbdload
       command refuses to work as a set-uid program.

EXIT VALUES
       Exit status is 0 if all tables could be loaded and/or all operations
       succeeded.  In the event of any I/O error (for example, attempting to
       load a table with the same name as one already loaded and accessible
       to the caller) or failure to load a table, exit status is 1 and a
       message is printed indicating the error.

CAVEATS
       Composite tables may be unloaded while they are actually in use
       without affecting current users, though new users may no longer
       attach to it.  This is because composite tables are copied and
       expanded when they are attached in order to keep state information
       related to the attaching user.  The ``original'' composite always has
       a zero reference count, and is never itself attached.  This is not
       strictly a bug, it's an ``anomaly''; the effect on the user is that a
       composite table may be attached and functional, yet not appear in the
       output of a kbdset query.

FILES
       /usr/lib/kbd        directory containing system standard map files

SEE ALSO
       kbdcomp(1M), kbdset(1), alp(7), attkbd(7).

















Licensed material--property of copyright holder(s)                         2


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