Re: tcpd remarks warning

[jml4 () CAM AC UK (John Line)]

Greg A. Woods wrote:
> It's interesting to note that the line continuation feature is *NOT*
> documented in the hosts_access(5) manual page.  Unless you've read the
> source you shouldn't even know that you can use "\<newline>" to continue
> a long entry onto the next line!  ;-)  [[ There is one hint in an
> example. ]]

Mmm... the hosts_access(5) man page I've got in front of me (for V7.6) says

     Each access control file consists of zero or more  lines  of
     text.  These lines are processed in order of appearance. The
     search terminates when a match is found.

     o    A newline character is ignored when it is preceded by a
          backslash  character. This permits you to break up long
          lines so that they are easier to edit.

It then goes on to say

     o    Blank lines or lines that begin with  a  `#'  character
          are  ignored.   This permits you to insert comments and
          whitespace so that the tables are easier to read.

If read carefully, that does make it clear that continuation lines are
re-joined *before* checking for comments. In reality, I suspect many people
will look down the list for the case they are interested in, and not
look at "irrelevant" items, missing the highly significant interaction.
Like so many UNIX man pages, it means precisely what it says, not what other
experience may lead people to expect/assume/take for granted. :-(

                                John Line

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John Line - Cambridge University Computing Service, Computer Laboratory,
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