Programming Internet Email
by David Wood


This errata page lists errors outstanding in the most recent printing.  

If you have any error reports or technical questions, you can send them to
booktech@oreilly.com. (Please specify the printing date of your copy.)


This page was last updated on January 3, 2007.


Here's a key to the markup:

        [page-number]: serious technical mistake
        {page-number}: minor technical mistake
        <page-number>: important language/formatting problem
        (page-number): language change or minor formatting problem
        ?page-number?: reader question or request for clarification


CONFIRMED errors:


(13) In the first paragraph, second line, the wrong word is used. It now
reads:

        "...connected but always..."

Should read:

        "...connected and always..."


(21) There is a spelling error in the 5th point from bottom. It now reads:

        "...formatted interace with..."

Should read:

        "...formatted interface with..."


{26} In paragraph 6, line 5, the wrong word is used. It now reads:

        "72 lines..."

Should read:

        "72 characters..."


(27) In paragraph 2, there is a confusing point in the discussion for 
splitting lines: The first occurrance of the string is "naturally" wrapped 
at the same point that the second one is manually split.  The following 
footnote should be added to this line:
                  
	"Note that this line is wrapped by the page layout, but that the 
	reader should consider it to be unbroken when reading the example."


(28) The last sentence of paragraph 6 now reads:

	"If it is present, it should reflect the actual author of the message."

It should read:

        "If it is present, it should reflect the person (or program) who 
	actually sent the message on behalf of the author."


(30) The last sentence of paragraph 4 now reads:

        "The real author is represented in the Sender header and the person 
	or program that actually sent the message is represented in the From 
	header."

It should read:

        "The real author is represented in the From header and the person or 
	program that actually sent the message is represented in the Sender 
	header."


{31} In the sample conversation, there is a line missing.

The SMTP DATA portion must be ended with a period (.) by itself on a
line (followed by CRLF as line delimiter, of course), in the first
column of the line. This line is not printed in the sample
conversation. The correct way would be:

        the message.
        .                    << This '.' is currently missing.
        250 (etc)


(31) The message at the bottom of the page is missing the 'To' header field.
CORRECTION: Change the last sentence of paragraph 3 from:
                  
	"Similarly, the To header gets written..."

to:

        "The MTA knows the message recipient from the RCPT TO: line. This 
	means that the message recipient is in the envelope, but there is no
        matching To: header in the message."


{33} The example telnet session is missing linebreaks. Two linebreaks
         should be inserted in the line beginning with 'Date:' after "+0400"
         and another linebreak after "action.", so that it looks like this:

                          Date: Fri, 32 Feb 1492 09:53:43 +0400

                          Testing of the Date header from a user action.
                          .


(49) Paragraph 4
Paragraph 4 reads:

"An octet is subtly different from a byte.  An octet is 
8 bits, where the earlier bits in the stream represent the 
most significance.  This is called 'big-endian' and is the 
Internet standard order, called the 'network standard byte 
order'.  A byte (8 bits), on the other hand, may be 
interpreted in one of two ways, big-endian or little-endian, 
and the manner of local interpretation is system dependent.  
Some computer systems use little-endian, where the earlier 
bits are interpreted as being the lower-order bits.  
Obviously, if you are on a little-endian system, encode a 
bit stream directly and send it to a big-endian system, 
the byte stream will not be correctly interpreted.   
Therefore, all bit streams must be converted to the network 
standard big-endian order (which yields an octet stream), 
prior to applying any type of MIME encoding."

and should be changed to read:

"An octet stream is subtly different from a bit stream.  
An octet is 8 bits, like an 8-bit byte.  The earlier octets 
in the stream represent the most significance.  This is 
called 'big-endian' and is the Internet standard order, 
called the 'network standard byte order'.  An 8-bit byte 
stream, on the other hand, may be interpreted in one of two 
ways, big-endian or little-endian, and the manner of local 
interpretation is system dependent.  Some computer systems 
use little-endian, where the earlier bytes are interpreted 
as being of lower-order.  Obviously, if you are on a little-
endian system, encode a bit stream directly and send it to 
a big-endian system, the stream will not be correctly 
interpreted.   Therefore, all bit streams must be converted 
to the network standard big-endian order (which yields an 
octet stream), prior to applying any type of MIME encoding."



(56,57) The bottom of page 56, top of page 57. The sample strings of
characters should be in constant-width font.


(74) The last sentence of the second paragraph from the bottom of the page
should read:

        "S/MIME uses algorithms which are restricted to weak (40-bit)
        cryptography outside of the United States for the time being.
        This is due to export restrictions imposed by the United States
        government."

A new paragraph should be added immediately after the above, which should 
read:                          

        "Both OpenPGP and S/MIME are affected by export restrictions on
        cryptographic products and algorithms.  PGP's international version
        (by some, though not all, accounts started by an improper export)
        gives OpenPGP a head start on developing a system of more than
        40-bit encryption across international borders."


(155) In the first line, "The Log out State" should be changed to "The Logout 
State." 
        

(163) Some explanation of the "~" in the SUBSCRIBE example (7th line from 
bottom of page) should be given, at least for the Win32 users.

For example, you could insert a paragraph immediately following the SUBSCRIBE 
example which reads:

	"Note that the '~' character used in the mailbox name is used under 
	Unix and Unix-like operating systems to refer to a user's home 
	directory."


(164) In the 2nd to last paragraph, change "A SUBSCRIBE command is then
use to mark" to "... is then used to mark..."


(169) In Table 11-8, the DELETED key has a surplus character: "DELETED>"
should be "DELETED".


(172)
In the IMAP FETCH example, the server tag returned should read
"DF56", not "a127".


(172)
In the paragraph under the IMAP FETCH example, the phrase "It
returned the date" should read "It returned the data".


(202) In the second line under the heading "Reading an Entry," change "fllow" 
to "follow."


(280) In the code, the comment "# Create the encoded content string, starting 
with the # newly-created MIME header" should either be in two lines (the 
second line starting "# newly-created..." or one line without the second '#'.
        

(287) In the code, "#fflush socket..." should read "# flush socket...".

        
(289)  In the third line under "Sending MIMEi Email via Java," change 
"shorted" to "shorter."


(325) In the first line of the 2nd full paragraph, change "it is makes" to 
"makes." 

        
(325) In the 4th line of the 5th full paragraph, change "did notlist" to "did 
not list." 
        

(330) Paragraph 4
Paragraph 4, sentance 4 should read,

"This approach seemed to have promise, but has not worked 
out as well as some have hoped.  This is due primarily
to the fact that the RBL is based upon IP addresses, 
blocking the orginating mail server (often an Internet Service
Provider).  According to the RBL rules for inclusion, only
those ISPs who operate an open mail relay will be blacklisted.
Unfortunately, this includes both those supporting spam and
those who are incapable or unwilling to restrict mail relaying
via their servers.  The RBL thus both reduces spam and generates
much abuse from many of those banned.

The remainder of the orginal paragraph should be deleted.


(341) RFCs 2425/2426 are listed in reverse order.


(348) 
Second column, eighth entry should be changed to 
include line breaks between the ten MIME types listed there.


(354) In the entry for MTA, change "deliverying" to "delivering."