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+@c This is part of the GNU Mailutils manual.
+@c Copyright (C) 1999,2000,2001,2002,2003,2004,2005,2006,2007,2008
+@c Free Software Foundation, Inc.
+@c See file mailutils.texi for copying conditions.
+@comment *******************************************************************
+@node Usage Vars
+@appendix Configuring Help Summary
+
+Running @command{@var{prog} --help} displays the short usage summary
+for @var{prog} utility (@pxref{Common Options}). This summary is
+organized by @dfn{groups} of semantically close options. The options
+within each group are printed in the following order: a short option,
+eventually followed by a list of corresponding long option names,
+followed by a short description of the option. For example, here is an
+excerpt from the actual @kbd{sieve --help} output:
+
+@verbatim
+  -c, --compile-only         Compile script and exit
+  -d, --debug[=FLAGS]        Debug flags
+  -e, --email=ADDRESS        Override user email address
+@end verbatim
+
+@vrindex ARGP_HELP_FMT, environment variable
+The exact visual representation of the help output is configurable via
+@env{ARGP_HELP_FMT} environment variable. The value of this variable
+is a comma-separated list of @dfn{format variable} assignments. There
+are two kinds of format variables. An @dfn{offset variable} keeps the
+offset of some part of help output text from the leftmost column on
+the screen. A @dfn{boolean} variable is a flag that toggles some
+output feature on or off. Depending on the type of the corresponding
+variable, there are two kinds of assignments:
+
+@table @asis
+@item Offset assignment
+
+The assignment to an offset variable has the following syntax:
+
+@smallexample
+@var{variable}=@var{value}
+@end smallexample
+
+@noindent
+where @var{variable} is the variable name, and @var{value} is a
+numeric value to be assigned to the variable.
+
+@item Boolean assignment
+
+To assign @code{true} value to a variable, simply put this variable name. To
+assign @code{false} value, prefix the variable name with @samp{no-}. For
+example:
+
+@smallexample
+@group
+# Assign @code{true} value:
+dup-args
+# Assign @code{false} value:
+no-dup-args
+@end group
+@end smallexample
+@end table
+
+Following variables are declared:
+
+@deftypevr {Help Output} boolean dup-args
+If true, arguments for an option are shown with both short and long
+options, even when a given option has both forms, for example:
+
+@smallexample
+  -e ADDRESS, --email=ADDRESS        Override user email address
+@end smallexample
+
+If false, then if an option has both short and long forms, the
+argument is only shown with the long one, for example:
+
+@smallexample
+  -e, --email=ADDRESS        Override user email address
+@end smallexample
+
+@noindent
+and a message indicating that the argument is applicable to both
+forms is printed below the options. This message can be disabled
+using @code{dup-args-note} (see below).
+
+The default is false.
+@end deftypevr
+
+@deftypevr {Help Output} boolean dup-args-note
+If this variable is true, which is the default, the following notice
+is displayed at the end of the help output:
+
+@quotation
+Mandatory or optional arguments to long options are also mandatory or
+optional for any corresponding short options.
+@end quotation
+
+Setting @code{no-dup-args-note} inhibits this message. Normally, only
+one of variables @code{dup-args} or @code{dup-args-note} should be set.
+@end deftypevr
+
+@deftypevr {Help Output} offset short-opt-col
+Column in which short options start. Default is 2.
+
+@smallexample
+@group
+$ @kbd{sieve --help|grep ADDRESS}
+  -e, --email=ADDRESS        Override user email address
+$ @kbd{ARGP_HELP_FMT=short-opt-col=6 sieve --help|grep ARCHIVE}
+      -e, --email=ADDRESS        Override user email address
+@end group
+@end smallexample
+@end deftypevr
+
+@deftypevr {Help Output} offset long-opt-col
+Column in which long options start. Default is 6. For example:
+
+@smallexample
+@group
+$ @kbd{sieve --help|grep ADDRESS}
+  -e, --email=ADDRESS        Override user email address
+$ @kbd{ARGP_HELP_FMT=long-opt-col=16 sieve --help|grep ADDRESS}
+  -e,           --email=ADDRESS        Override user email address
+@end group
+@end smallexample
+@end deftypevr
+
+@deftypevr {Help Output} offset doc-opt-col
+Column in which @dfn{doc options} start.  A doc option isn't actually
+an option, but rather an arbitrary piece of documentation that is
+displayed in much the same manner as the options.  For example, in
+the output of @command{folder --help}:
+
+@verbatim
+Usage: folder [OPTION...] [action] [msg]
+GNU MH folder
+  Actions are:
+      --list                 List the contents of the folder stack
+  ...
+@end verbatim
+
+@noindent
+the string @samp{Actions are:} is a doc option.  Thus, if you set
+@kbd{ARGP_HELP_FMT=doc-opt-col=6} the above part of the help output
+will look as follows:
+
+@verbatim
+Usage: folder [OPTION...] [action] [msg]
+GNU MH folder
+      Actions are:
+      --list                 List the contents of the folder stack
+  ...
+@end verbatim
+@end deftypevr
+
+@deftypevr {Help Output} offset opt-doc-col
+Column in which option description starts. Default is 29.
+
+@smallexample
+@group
+$ @kbd{sieve --help|grep ADDRESS}
+  -e, --email=ADDRESS        Override user email address
+$ @kbd{ARGP_HELP_FMT=opt-doc-col=19 sieve --help|grep ADDRESS}
+  -e, --email=ADDRESS   Override user email address
+$ @kbd{ARGP_HELP_FMT=opt-doc-col=9 sieve --help|grep -i ADDRESS}
+  -e, --email=ADDRESS
+         Override user email address
+@end group
+@end smallexample
+
+@noindent
+Notice, that the description starts on a separate line if
+@code{opt-doc-col} value is too small.
+@end deftypevr
+
+@deftypevr {Help Output} offset header-col
+Column in which @dfn{group headers} are printed.  A group header is a
+descriptive text preceding an option group.  For example, in the
+following text:
+
+@verbatim
+ Sieve options
+  -I, --includedir=DIR       Append directory DIR to the
+                             list of include directories
+@end verbatim
+@noindent
+the text @samp{Sieve options} is a group header.
+
+The default value is 1.
+@end deftypevr
+
+@deftypevr {Help Output} offset usage-indent
+Indentation of wrapped usage lines. Affects @option{--usage}
+output. Default is 12.
+@end deftypevr
+
+@deftypevr {Help Output} offset rmargin
+Right margin of the text output. Used for wrapping.
+@end deftypevr