Index: getopt_long.3
===================================================================
--- getopt_long.3
+++ getopt_long.3
@@ -31,7 +31,7 @@
 .\"     @(#)getopt.3	8.5 (Berkeley) 4/27/95
 .\" $FreeBSD$
 .\"
-.Dd December 25, 2011
+.Dd January 31, 2018
 .Dt GETOPT_LONG 3
 .Os
 .Sh NAME
@@ -213,6 +213,31 @@
 .Ql \&?
 if the user specified an unknown or ambiguous option, and
 \-1 when the argument list has been exhausted.
+Warnings about missing option arguments will be suppressed if a leading
+.Ql \&:
+is specified in
+.Fa optstr .
+.Pp
+In addition to
+.Ql \&: ,
+a leading
+.Ql \&+
+or
+.Ql \&-
+in
+.Fa optstr
+also has special meaning.
+A leading
+.Ql \&+
+indicates that all non-option arguments should be permuted to the end of argv,
+rather than halting processing at the first non-option argument.
+A leading
+.Ql \&-
+indicates that all non-option arguments should be treated as if they are
+arguments to a literal
+.Ql \&1
+flag (i.e., the function call will return the value 1, rather than the char
+literal '1').
 .Sh ENVIRONMENT
 .Bl -tag -width ".Ev POSIXLY_CORRECT"
 .It Ev POSIXLY_CORRECT