===================================================================
RCS file: /cvs/mandoc/roff.7,v
retrieving revision 1.53
retrieving revision 1.56
diff -u -p -r1.53 -r1.56
--- mandoc/roff.7	2014/04/07 15:07:13	1.53
+++ mandoc/roff.7	2014/08/13 20:34:29	1.56
@@ -1,4 +1,4 @@
-.\"	$Id: roff.7,v 1.53 2014/04/07 15:07:13 schwarze Exp $
+.\"	$Id: roff.7,v 1.56 2014/08/13 20:34:29 kristaps Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010, 2011, 2013, 2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: April 7 2014 $
+.Dd $Mdocdate: August 13 2014 $
 .Dt ROFF 7
 .Os
 .Sh NAME
@@ -239,8 +239,9 @@ pica (~1/6 inch)
 .It p
 point (~1/72 inch)
 .It f
-synonym for
+scale
 .Sq u
+by 65536
 .It v
 default vertical span
 .It m
@@ -254,7 +255,7 @@ width of rendered
 .Pq en
 character
 .It u
-default horizontal span
+default horizontal span for the terminal
 .It M
 mini-em (~1/100 em)
 .El
@@ -262,7 +263,6 @@ mini-em (~1/100 em)
 Using anything other than
 .Sq m ,
 .Sq n ,
-.Sq u ,
 or
 .Sq v
 is necessarily non-portable across output media.
@@ -409,24 +409,21 @@ and the number of arguments is not checked.
 Append to a macro definition.
 The syntax of this request is the same as that of
 .Sx \&de .
-It is currently ignored by
-.Xr mandoc 1 ,
-as are its children.
 .Ss \&ami
 Append to a macro definition, specifying the macro name indirectly.
 The syntax of this request is the same as that of
 .Sx \&dei .
-It is currently ignored by
-.Xr mandoc 1 ,
-as are its children.
 .Ss \&am1
 Append to a macro definition, switching roff compatibility mode off
 during macro execution.
 The syntax of this request is the same as that of
 .Sx \&de1 .
-It is currently ignored by
-.Xr mandoc 1 ,
-as are its children.
+Since
+.Xr mandoc 1
+does not implement
+.Nm
+compatibility mode at all, it handles this request as an alias for
+.Sx \&am .
 .Ss \&as
 Append to a user-defined string.
 The syntax of this request is the same as that of
@@ -554,9 +551,13 @@ Define a
 macro, specifying the macro name indirectly.
 The syntax of this request is the same as that of
 .Sx \&de .
-It is currently ignored by
-.Xr mandoc 1 ,
-as are its children.
+The request
+.Pp
+.D1 Pf . Cm \&dei Ar name Op Ar end
+.Pp
+has the same effect as:
+.Pp
+.D1 Pf . Cm \&de No \e* Ns Bo Ar name Bc Op \e* Ns Bq Ar end
 .Ss \&de1
 Define a
 .Nm
@@ -1172,10 +1173,15 @@ Digit width space character.
 Anchor definition; ignored by
 .Xr mandoc 1 .
 .Ss \eB\(aq Ns Ar string Ns \(aq
-Test whether
+Interpolate
+.Sq 1
+if
 .Ar string
-is a numerical expession; ignored by
-.Xr mandoc 1 .
+conforms to the syntax of
+.Sx Numerical expressions
+explained above and
+.Sq 0
+otherwise.
 .Ss \eb\(aq Ns Ar string Ns \(aq
 Bracket building function; ignored by
 .Xr mandoc 1 .
@@ -1299,9 +1305,13 @@ Vertical motion; ignored by
 .Xr mandoc 1 .
 .Ss \ew\(aq Ns Ar string Ns \(aq
 Interpolate the width of the
-.Ar string ;
-ignored by
-.Xr mandoc 1 .
+.Ar string .
+The
+.Xr mandoc 1
+implementation assumes that after expansion of user-defined strings, the
+.Ar string
+only contains normal characters, no escape sequences, and that each
+character has a width of 24 basic units.
 .Ss \eX\(aq Ns Ar string Ns \(aq
 Output
 .Ar string
@@ -1337,6 +1347,12 @@ The term
 refers to groff version 1.15.
 .Pp
 .Bl -dash -compact
+.It
+The
+.Sq u
+scaling unit is the default terminal unit.
+In traditional troff systems, this unit would change depending on the
+output media.
 .It
 In mandoc, the
 .Sx \&EQ ,