uniq does not allow using the -c option (print counts) with -d (or -u). Now this is acceptable according to open group spec, but both GNU, OpenBSD and NetBSD allow it, and -d -c is useful to get the non 1 counts (-u -c is not that useful...). Google shows it is a pretty common use, so would be nice to support it.
A commit references this bug: Author: emaste Date: Mon May 15 20:18:14 UTC 2017 New revision: 318316 URL: https://svnweb.freebsd.org/changeset/base/318316 Log: uniq: allow -c to be used with -d or -u Bring in some bits from NetBSD and lift the restriction in uniq(1) that -c cannot be used with the -d and -u options. This restriction seems unnecessary and is supported at least by GNU, OpenBSD, and NetBSD. Lift the restriction and simplify the show() logic a little bit to maintain functionality when -c is provided with -d/-u. Also with this change, -d and -u are now actually a mutually exclusive, albeit valid, combination. Given that they both indicate opposite behavior, uniq(1) will no longer output anything if both -d and -u are supplied. This is in line with NetBSD as well as GNU. Adjust the man page and usage() to reflect that -c is its own standalone option. PR: 200553 Submitted by: Kyle Evans <kevans91@ksu.edu> Reviewed by: cem, emaste MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D10694 Changes: head/usr.bin/uniq/uniq.1 head/usr.bin/uniq/uniq.c
A commit references this bug: Author: emaste Date: Tue May 30 16:55:16 UTC 2017 New revision: 319226 URL: https://svnweb.freebsd.org/changeset/base/319226 Log: MFC r318316: uniq: allow -c to be used with -d or -u Bring in some bits from NetBSD and lift the restriction in uniq(1) that -c cannot be used with the -d and -u options. This restriction seems unnecessary and is supported at least by GNU, OpenBSD, and NetBSD. Lift the restriction and simplify the show() logic a little bit to maintain functionality when -c is provided with -d/-u. Also with this change, -d and -u are now actually a mutually exclusive, albeit valid, combination. Given that they both indicate opposite behavior, uniq(1) will no longer output anything if both -d and -u are supplied. This is in line with NetBSD as well as GNU. Adjust the man page and usage() to reflect that -c is its own standalone option. PR: 200553 Submitted by: Kyle Evans <kevans91@ksu.edu> Changes: _U stable/11/ stable/11/usr.bin/uniq/uniq.1 stable/11/usr.bin/uniq/uniq.c