illumos gate

The changes are as following:
(1) Remove unnecessary macros: e.g., .LP after .SS;
(2) Revamp Example 3:

a)

       When standard input is a terminal, the following command gets two
       arbitrary pieces of input from the terminal with a single invocation of
       cat:

         example% cat start - middle - end > file

       when standard input is a terminal, gets two arbitrary pieces of input
       from the terminal with a single invocation of cat.

Remove the second duplicated "when standard input ....":

       when standard input is a terminal, gets two arbitrary pieces of input
       from the terminal with a single invocation of cat.

b)

       If standard input is a regular file,

         example% cat start - middle - end > file

       would be equivalent to the following command:

         cat start - middle /dev/null end > file

Add "example% " for second cat command:

       ......

       would be equivalent to the following command:

         example% cat start - middle /dev/null end > file

c)

       because the entire contents of the file would be consumed by cat the
       first time - was used as a file operand and an end-of-file condition
       would be detected immediately when -was referenced the second time.

There should be space between "-" and "was" in last sentence:

       ......
       would be detected immediately when - was referenced the second time.