859 .It
860 In page header lines, GNU troff versions up to and including 1.21
861 only print
862 .Ar volume
863 names explicitly specified in the
864 .Sx \&TH
865 macro; mandoc and newer groff print the default volume name
866 corresponding to the
867 .Ar section
868 number when no
869 .Ar volume
870 is given, like in
871 .Xr mdoc 5 .
872 .El
873 .Pp
874 The
875 .Sx OP
876 macro is part of the extended
877 .Nm
878 macro set, and may not be portable to non-GNU troff implementations.
879 .Sh SEE ALSO
880 .Xr man 1 ,
881 .Xr mandoc 1 ,
882 .Xr eqn 5 ,
883 .Xr mandoc_char 5 ,
884 .Xr mdoc 5 ,
885 .Xr roff 5 ,
886 .Xr tbl 5
887 .Sh HISTORY
888 The
889 .Nm
890 language first appeared as a macro package for the roff typesetting
891 system in
892 .At v7 .
893 It was later rewritten by James Clark as a macro package for groff.
894 Eric S. Raymond wrote the extended
895 .Nm
896 macros for groff in 2007.
897 The stand-alone implementation that is part of the
898 .Xr mandoc 1
|
859 .It
860 In page header lines, GNU troff versions up to and including 1.21
861 only print
862 .Ar volume
863 names explicitly specified in the
864 .Sx \&TH
865 macro; mandoc and newer groff print the default volume name
866 corresponding to the
867 .Ar section
868 number when no
869 .Ar volume
870 is given, like in
871 .Xr mdoc 5 .
872 .El
873 .Pp
874 The
875 .Sx OP
876 macro is part of the extended
877 .Nm
878 macro set, and may not be portable to non-GNU troff implementations.
879 .Sh INTERFACE STABILITY
880 .Nm "Obsolete Committed" .
881 .Sh SEE ALSO
882 .Xr man 1 ,
883 .Xr mandoc 1 ,
884 .Xr eqn 5 ,
885 .Xr mandoc_char 5 ,
886 .Xr mdoc 5 ,
887 .Xr roff 5 ,
888 .Xr tbl 5
889 .Sh HISTORY
890 The
891 .Nm
892 language first appeared as a macro package for the roff typesetting
893 system in
894 .At v7 .
895 It was later rewritten by James Clark as a macro package for groff.
896 Eric S. Raymond wrote the extended
897 .Nm
898 macros for groff in 2007.
899 The stand-alone implementation that is part of the
900 .Xr mandoc 1
|