Clarify that .Ta as a line macro is a portability problem,

[mandoc.git] / roff.7

diff --git a/roff.7 b/roff.7
index 056587a67ee3ad9daab187d2afa06e393fd06e27..ab3a4b44cd5b16a63eee25c56b79cf2ab8d06787 100644 (file)
--- a/roff.7
+++ b/roff.7
@@ -1,4 +1,4 @@
-.\"    $Id: roff.7,v 1.84 2017/06/04 22:44:15 schwarze Exp $
+.\"    $Id: roff.7,v 1.93 2017/06/14 23:24:17 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010,2011,2013-2015,2017 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: June 4 2017 $
+.Dd $Mdocdate: June 14 2017 $
 .Dt ROFF 7
 .Os
 .Sh NAME
@@ -412,7 +412,6 @@ Create an alias for a number register.
 Currently unsupported.
 .It Ic \&als Ar newname oldname
 Create an alias for a request, string, macro, or diversion.
-Currently unsupported.
 .It Ic \&am Ar macroname Op Ar endmacro
 Append to a macro definition.
 The syntax of this request is the same as that of
@@ -527,7 +526,10 @@ Trailing characters are ignored.
 Center the next
 .Ar N
 input lines without filling.
-Currently ignored.
+.Ar N
+defaults to 1.
+An argument of 0 or less ends centering.
+Currently, high level macros abort centering.
 .It Ic \&cf Ar filename
 Output the contents of a file.
 Ignored because insecure.
@@ -1042,8 +1044,6 @@ If the first character of
 is
 .Sq c
 .Pq character available ,
-.Sq d
-.Pq string defined ,
 .Sq e
 .Pq even page ,
 .Sq t
@@ -1056,6 +1056,15 @@ it evaluates to false.
 If the first character of
 .Ar condition
 is
+.Sq d ,
+it evaluates to true if the rest of
+.Ar condition
+is the name of an existing user defined macro or string;
+otherwise, it evaluates to false.
+.It
+If the first character of
+.Ar condition
+is
 .Sq r ,
 it evaluates to true if the rest of
 .Ar condition
@@ -1432,8 +1441,15 @@ Currently ignored.
 Print all number registers on standard error output.
 Currently ignored.
 .It Ic \&po Op Oo Cm + Ns | Ns Cm - Oc Ns Ar offset
-Set horizontal page offset.
-Currently ignored.
+Set a horizontal page offset.
+If no argument is specified, the page offset is reverted to its
+previous value.
+If a sign is specified, the new page offset is calculated relative
+to the current one; otherwise, it is absolute.
+The argument follows the syntax of
+.Sx Scaling Widths
+and the default scaling unit is
+.Cm m .
 .It Ic \&ps Op Oo Cm + Ns | Ns Cm - Oc Ns size
 Change point size.
 Currently ignored.
@@ -1474,12 +1490,23 @@ This is a Heirloom extension and currently ignored.
 Justify the next
 .Ar N
 input lines to the right margin without filling.
-Currently ignored.
+.Ar N
+defaults to 1.
+An argument of 0 or less ends right adjustment.
 .It Ic \&rm Ar macroname
 Remove a request, macro or string.
 .It Ic \&rn Ar oldname newname
 Rename a request, macro, diversion, or string.
-Currently unsupported.
+In
+.Xr mandoc 1 ,
+user-defined macros,
+.Xr mdoc 7
+and
+.Xr man 7
+macros, and user-defined strings can be renamed, but renaming of
+predefined strings and of
+.Nm
+requests is not supported, and diversions are not implemented at all.
 .It Ic \&rnn Ar oldname newname
 Rename a number register.
 Currently unsupported.
@@ -1771,7 +1798,7 @@ logical and (corresponds to C
 .Ic && )
 .It Ic \&:
 logical or (corresponds to C
-.Ic \&|| )
+.Ic || )
 .It Ic <?
 minimum (not available in C)
 .It Ic >?
@@ -1929,8 +1956,11 @@ and
 .Ss \eH\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
 Set the height of the current font; ignored by
 .Xr mandoc 1 .
-.Ss \eh\(aq Ns Ar width Ns \(aq
-Horizontal motion relative to the current position.
+.Ss \eh\(aq Ns Oo Cm \&| Oc Ns Ar width Ns \(aq
+Horizontal motion.
+If the vertical bar is given, the motion is relative to the current
+indentation.
+Otherwise, it is relative to the current position.
 The default scaling unit is
 .Cm m .
 .Ss \ek[ Ns Ar name ]
@@ -1979,6 +2009,8 @@ Overstrike, writing all the characters contained in the
 to the same output position.
 In terminal and HTML output modes,
 only the last one of the characters is visible.
+.Ss \ep
+Break the output line at the end of the current word.
 .Ss \eR\(aq Ns Ar name Oo +|- Oc Ns Ar number Ns \(aq
 Set number register; ignored by
 .Xr mandoc 1 .