Add some useful examples to the sed man page.

Reviewed by:	wblock, bcr
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D9958

usr.bin/sed/sed.1

@@ -31,7 +31,7 @@
 .\"	@(#)sed.1	8.2 (Berkeley) 12/30/93
 .\" $FreeBSD$
 .\"
-.Dd May 10, 2016
+.Dd March 27, 2017
 .Dt SED 1
 .Os
 .Sh NAME
@@ -586,6 +586,36 @@ as described in
 .Xr environ 7 .
 .Sh EXIT STATUS
 .Ex -std
+.Sh EXAMPLES
+Replace
+.Ql bar
+with
+.Ql baz
+when piped from another command:
+.Bd -literal -offset indent
+echo "An alternate word, like bar, is sometimes used in examples." | sed 's/bar/baz/'
+.Ed
+.Pp
+Using backlashes can sometimes be hard to read and follow:
+.Bd -literal -offset indent
+echo "/home/example" | sed  's/\\/home\\/example/\\/usr\\/local\\/example/'
+.Ed
+.Pp
+Using a different separator can be handy when working with paths:
+.Bd -literal -offset indent
+echo "/home/example" | sed 's#/home/example#/usr/local/example#'
+.Ed
+.Pp
+Replace all occurances of
+.Ql foo
+with
+.Ql bar
+in the file
+.Pa test.txt ,
+without creating a backup of the file:
+.Bd -literal -offset indent
+sed -i '' -e 's/foo/bar/' test.txt
+.Ed
 .Sh SEE ALSO
 .Xr awk 1 ,
 .Xr ed 1 ,