/usr/lib/swi-prolog/library/dialect/ is in swi-prolog-nox 5.10.4-3ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/swi-prolog/library/dialect/ciao/
/usr/lib/swi-prolog/library/dialect/ciao.pl
/usr/lib/swi-prolog/library/dialect/ciao/aggregates.pl
/usr/lib/swi-prolog/library/dialect/ciao/assertions.pl
/usr/lib/swi-prolog/library/dialect/ciao/classic.pl
/usr/lib/swi-prolog/library/dialect/ciao/engine/
/usr/lib/swi-prolog/library/dialect/ciao/engine/hiord_rt.pl
/usr/lib/swi-prolog/library/dialect/ciao/engine/internals.pl
/usr/lib/swi-prolog/library/dialect/ciao/format.pl
/usr/lib/swi-prolog/library/dialect/ciao/iso_misc.pl
/usr/lib/swi-prolog/library/dialect/ciao/isomodes.pl
/usr/lib/swi-prolog/library/dialect/ciao/lists.pl
/usr/lib/swi-prolog/library/dialect/ciao/read.pl
/usr/lib/swi-prolog/library/dialect/ciao/regtypes.pl
/usr/lib/swi-prolog/library/dialect/ciao/sockets.pl
/usr/lib/swi-prolog/library/dialect/ciao/strings.pl
/usr/lib/swi-prolog/library/dialect/ciao/system.pl
/usr/lib/swi-prolog/library/dialect/ciao/terms.pl
/usr/lib/swi-prolog/library/dialect/ciao/write.pl
/usr/lib/swi-prolog/library/dialect/commons.pl
/usr/lib/swi-prolog/library/dialect/hprolog.pl
/usr/lib/swi-prolog/library/dialect/iso/
/usr/lib/swi-prolog/library/dialect/iso/iso_predicates.pl
/usr/lib/swi-prolog/library/dialect/sicstus/
/usr/lib/swi-prolog/library/dialect/sicstus.pl
/usr/lib/swi-prolog/library/dialect/sicstus/arrays.pl
/usr/lib/swi-prolog/library/dialect/sicstus/block.pl
/usr/lib/swi-prolog/library/dialect/sicstus/lists.pl
/usr/lib/swi-prolog/library/dialect/sicstus/sockets.pl
/usr/lib/swi-prolog/library/dialect/sicstus/swipl-lfr.pl
/usr/lib/swi-prolog/library/dialect/sicstus/system.pl
/usr/lib/swi-prolog/library/dialect/sicstus/timeout.pl
/usr/lib/swi-prolog/library/dialect/yap/
/usr/lib/swi-prolog/library/dialect/yap.pl
/usr/lib/swi-prolog/library/dialect/yap/README.TXT