You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
287 lines
13 KiB
287 lines
13 KiB
<HTML>
|
|
<HEAD>
|
|
<TITLE> DwPopClient Man Page </TITLE>
|
|
</HEAD>
|
|
<BODY BGCOLOR="#FFFFFF">
|
|
<H2>
|
|
<FONT COLOR="navy"> NAME </FONT>
|
|
</H2>
|
|
<P>
|
|
DwPopClient -- Class for handling the client side of a POP session
|
|
<H2>
|
|
<FONT COLOR="navy"> SYNOPSIS </FONT>
|
|
</H2>
|
|
<PRE>class DW_EXPORT DwPopClient : public <A HREF="protocol.html">DwProtocolClient</A> {
|
|
|
|
public:
|
|
|
|
enum {
|
|
kCmdNoCommand=0,
|
|
kCmdUser,
|
|
kCmdPass,
|
|
kCmdQuit,
|
|
kCmdStat,
|
|
kCmdList,
|
|
kCmdRetr,
|
|
kCmdDele,
|
|
kCmdNoop,
|
|
kCmdRset,
|
|
kCmdApop,
|
|
kCmdTop,
|
|
kCmdUidl
|
|
};
|
|
<A HREF="pop.html#DwPopClient">DwPopClient</A>();
|
|
virtual ~DwPopClient();
|
|
virtual int <A HREF="pop.html#Open">Open</A>(const char* aServer, DwUint16 aPort=110);
|
|
DwObserver* <A HREF="pop.html#SetObserver">SetObserver</A>(DwObserver* aObserver);
|
|
int <A HREF="pop.html#StatusCode">StatusCode</A>() const;
|
|
const DwString& <A HREF="pop.html#SingleLineResponse">SingleLineResponse</A>() const;
|
|
const DwString& <A HREF="pop.html#MultiLineResponse">MultiLineResponse</A>() const;
|
|
int <A HREF="pop.html#User">User</A>(const char* aName);
|
|
int Pass(const char* a<A HREF="pop.html#Pass">Pass</A>wd);
|
|
int <A HREF="pop.html#Quit">Quit</A>();
|
|
int <A HREF="pop.html#Stat">Stat</A>();
|
|
int <A HREF="pop.html#List">List</A>();
|
|
int <A HREF="pop.html#List">List</A>(int aMsg);
|
|
int <A HREF="pop.html#Retr">Retr</A>(int aMsg);
|
|
int <A HREF="pop.html#Dele">Dele</A>(int aMsg);
|
|
int <A HREF="pop.html#Noop">Noop</A>();
|
|
int <A HREF="pop.html#Rset">Rset</A>();
|
|
int <A HREF="pop.html#Apop">Apop</A>(const char* aName, const char* aDigest);
|
|
int <A HREF="pop.html#Top">Top</A>(int aMsg, int aNumLines);
|
|
int <A HREF="pop.html#Uidl">Uidl</A>();
|
|
int <A HREF="pop.html#Uidl">Uidl</A>(int aMsg);
|
|
};
|
|
</PRE>
|
|
<H2>
|
|
<FONT COLOR="navy"> DESCRIPTION </FONT>
|
|
</H2>
|
|
<P>
|
|
<B><TT>DwPopClient</TT></B> is a class that handles the client side of a
|
|
POP session. Specifically, <B><TT>DwPopClient</TT></B> provides facilities
|
|
for opening a connection to a POP server, sending commands to the server,
|
|
receiving responses from the server, and closing the connection. The protocol
|
|
implemented is the Post Office Protocol version 3, as specified in RFC-1939.
|
|
<P>
|
|
<B><TT>DwPopClient</TT></B> is derived from
|
|
<B><TT><A HREF="protocol.html">DwProtocolClient</A></TT></B>. For information
|
|
about inherited member functions, especially member functions for detecting
|
|
failures or errors, see the man page for
|
|
<B><TT>DwProtocolClient</TT></B>.
|
|
<P>
|
|
In a POP session, the client sends commands to the server and receives responses
|
|
from the server. A client command consists of a command word and zero or
|
|
more argument words. A server response consists of a single line status response,
|
|
which may be followed immediately by a multi-line response. The first word
|
|
of the status response is either +OK or -ERR, indicating the success or failure
|
|
of the command. The status line may also contain other information requested
|
|
by the client.
|
|
<P>
|
|
<B><TT>DwPopClient</TT></B> has only a default constructor. On Win32 platforms,
|
|
it is possible for the constructor to fail. (It calls WSAStartup().) You
|
|
should verify that the constructor succeeded by calling the inherited member
|
|
function <B><TT>DwProtocolClient::LastError()</TT></B> and checking for a
|
|
zero return value.
|
|
<P>
|
|
To open a connection to the server, call the member function
|
|
<B><TT>Open()</TT></B> with the name of the server as an argument.
|
|
<B><TT>Open()</TT></B> accepts an optional argument that specifies the TCP
|
|
port that the server listens to. The default port is the standard POP port
|
|
(110). <B><TT>Open()</TT></B> may fail, so you should check the return value
|
|
to verify that it succeeded. To close the connection, call the inherited
|
|
member function <B><TT>DwProtocolClient::Close()</TT></B>. To check if a
|
|
connection is open, call the inherited member function
|
|
<B><TT>DwProtocolClient::IsOpen()</TT></B>. <B><TT>IsOpen()</TT></B> returns
|
|
a boolean value that indicates whether or not a call to
|
|
<B><TT>Open()</TT></B> was successful; it will not detect failure in the
|
|
network or a close operation by the remote host.
|
|
<P>
|
|
For each POP command, <B><TT>DwPopClient</TT></B> has a member function that
|
|
sends that command and receives the server's response. If the command takes
|
|
any arguments, then those arguments are passed as function arguments to the
|
|
command function. The command functions return the first character of the
|
|
server's response, which will be '+' if the command succeeded or '-' if the
|
|
command failed. In some cases, because of a communications error or some
|
|
other error, it is not possible for the command function to send the command
|
|
or receive the response. When this happens, the command function will return
|
|
0. You can determine the precise error or failure by calling the inherited
|
|
member functions <B><TT>DwProtocolClient::LastError()</TT></B> or
|
|
<B><TT>DwProtocolClient::LastFailure()</TT></B>.
|
|
<P>
|
|
After each command is sent, <B><TT>DwPopClient</TT></B> receives the server's
|
|
response and remembers it. The member function
|
|
<B><TT>StatusCode()</TT></B> returns the first character of the server's
|
|
status response; it will be '+' or '-', indicating success or failure, or
|
|
zero if no response was received from the server.
|
|
<B><TT>SingleLineResponse()</TT></B> returns the entire single line status
|
|
response from the server, including the initial "+OK" or "-ERR" status word.
|
|
<P>
|
|
The server sends a single-line response, including a status code, for all
|
|
POP commands. For some commands, such as when the client requests a mail
|
|
message, the server sends a multi-line text response immediately following
|
|
the single-line status response. Multi-line text responses can be received
|
|
in either of two ways. The simplest way is to call the member function
|
|
<B><TT>MultiLineResponse()</TT></B> after a command completes successfully.
|
|
This simple method works fine for non-interactive applications. It can be
|
|
a problem in interactive applications, however, because there is no data
|
|
to display to a user until the entire multi-line response is retrieved. An
|
|
alternative method allows your program to retrieve the multi-line response
|
|
one line at a time as it is received. To use this method, you must define
|
|
a subclass of <B><TT>DwObserver</TT></B> and assign an object of that class
|
|
to the <B><TT>DwPopClient</TT></B> object using the member function
|
|
<B><TT>SetObserver()</TT></B>. <B><TT>DwObserver</TT></B> is an abstract
|
|
class, declared in protocol.h, that has just one pure virtual member function
|
|
<B><TT>Notify()</TT></B>. After each line of the multi-line response is received,
|
|
<B><TT>DwPopClient</TT></B> will call the <B><TT>Notify()</TT></B> member
|
|
function of its assigned <B><TT>DwObserver</TT></B> object. Each invocation
|
|
of <B><TT>Notify()</TT></B> should call the <B><TT>DwPopClient</TT></B> member
|
|
function <B><TT>MultiLineResponse()</TT></B> to retrieve the next line of
|
|
the text response. Note that you cannot use both of these methods at the
|
|
same time: if an observer is assigned,
|
|
<B><TT>MultiLineResponse()</TT></B> returns only the last line received,
|
|
not the entire multi-line response.
|
|
<H2>
|
|
<FONT COLOR="navy"> Public Member Functions </FONT>
|
|
</H2>
|
|
<P>
|
|
<FONT COLOR="teal"><B> <A NAME="DwPopClient">DwPopClient</A>() </B></FONT>
|
|
<P>
|
|
Initializes the <B><TT>DwPopClient</TT></B> object. It is possible for the
|
|
constructor to fail. To verify that the constructor succeeded, call the member
|
|
function <B><TT>LastError()</TT></B> and check that it returns zero. (In
|
|
the Win32 implementation, the constructor calls the Winsock function
|
|
<B><TT>WSAStartup()</TT></B>, which may fail.)
|
|
<P>
|
|
<FONT COLOR="teal"><B> virtual int <A NAME="Open">Open</A>(const char* aServer,
|
|
DwUint16 aPort=110) </B></FONT>
|
|
<P>
|
|
Opens a TCP connection to the server <B><TT>aServer</TT></B> at port
|
|
<B><TT>aPort</TT></B>. <B><TT>aServer</TT></B> may be either a host name,
|
|
such as "news.acme.com" or an IP number in dotted decimal format, such as
|
|
"147.81.64.60". The default value for <B><TT>aPort</TT></B> is 110, the
|
|
well-known port for POP3 assigned by the Internet Assigned Numbers Authority
|
|
(IANA).
|
|
<P>
|
|
If the connection attempt succeeds, the server sends a response.
|
|
<B><TT>Open()</TT></B> returns the server's status code ('+' or '-'). The
|
|
full response from the server can be retrieved by calling
|
|
<B><TT>SingleLineResponse()</TT></B>.
|
|
<P>
|
|
If the connection attempt fails, <B><TT>Open()</TT></B> returns 0. To determine
|
|
what error occurred when a connection attempt fails, call the inherited member
|
|
function <B><TT>DwProtocolClient::LastError()</TT></B>. To determine if a
|
|
failure also occurred, call the inherited member function
|
|
<B><TT>DwProtocolClient::LastFailure()</TT></B>.
|
|
<P>
|
|
<FONT COLOR="teal"><B> DwObserver*
|
|
<A NAME="SetObserver">SetObserver</A>(DwObserver* aObserver) </B></FONT>
|
|
<P>
|
|
Sets the observer object that interacts with the
|
|
<B><TT>DwPopClient</TT></B> object to retrieve a multi-line response. If
|
|
an observer is set, <B><TT>DwPopClient</TT></B> will call the observer's
|
|
<B><TT>Notify()</TT></B> method after each line of the multi-line response
|
|
is received. To remove an observer, call <B><TT>SetObserver()</TT></B> with
|
|
a NULL argument. <B><TT>SetObserver()</TT></B> returns the previously set
|
|
observer, or NULL if no observer was previously set.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="StatusCode">StatusCode</A>() const
|
|
</B></FONT>
|
|
<P>
|
|
Returns the status code received from the server in response to the last
|
|
client command. The status codes in POP3 are '+', indicating success, and
|
|
'-', indicating failure. If no response was received,
|
|
<B><TT>StatusCode()</TT></B> returns zero.
|
|
<P>
|
|
<FONT COLOR="teal"><B> const DwString&
|
|
<A NAME="SingleLineResponse">SingleLineResponse</A>() const </B></FONT>
|
|
<P>
|
|
Returns the single line status response last received from the server. If
|
|
no response was received, perhaps because of a communications failure,
|
|
<B><TT>SingleLineResponse()</TT></B> returns an empty string.
|
|
<P>
|
|
<FONT COLOR="teal"><B> const DwString&
|
|
<A NAME="MultiLineResponse">MultiLineResponse</A>() const </B></FONT>
|
|
<P>
|
|
If no observer is set for this object,
|
|
<B><TT>MultiLineResponse()</TT></B> returns a string that comprises the entire
|
|
sequence of lines received from the server. Otherwise, if an observer
|
|
<I>is</I> set for this object, <B><TT>MultiLineResponse()</TT></B> returns
|
|
only the most recent line received.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="User">User</A>(const char* aName)
|
|
</B></FONT>
|
|
<P>
|
|
Sends the USER command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<B><TT>aName</TT></B> is the name of the user, which is sent in the command.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Pass">Pass</A>(const char* aPasswd)
|
|
</B></FONT>
|
|
<P>
|
|
Sends the PASS command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<B><TT>aPasswd</TT></B> is the password, which is sent in the command.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Quit">Quit</A>() </B></FONT>
|
|
<P>
|
|
Sends the QUIT command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Stat">Stat</A>() </B></FONT>
|
|
<P>
|
|
Sends the STAT command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="List">List</A>() <BR>
|
|
int List(int aMsg) </B></FONT>
|
|
<P>
|
|
Sends the LIST command, with or without a message number, and returns the
|
|
status code received from the server. If no response is received, the function
|
|
returns zero.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Retr">Retr</A>(int aMsg) </B></FONT>
|
|
<P>
|
|
Sends the RETR command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<B><TT>aMsg</TT></B> is the message number, which is sent in the command.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Dele">Dele</A>(int aMsg) </B></FONT>
|
|
<P>
|
|
Sends the DELE command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<B><TT>aMsg</TT></B> is the message number, which is sent in the command.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Noop">Noop</A>() </B></FONT>
|
|
<P>
|
|
Sends the NOOP command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Rset">Rset</A>() </B></FONT>
|
|
<P>
|
|
Sends the RSET command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Apop">Apop</A>(const char* aName, const
|
|
char* aDigest) </B></FONT>
|
|
<P>
|
|
Sends the APOP command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<B><TT>aName</TT></B> is the name of the user, which is sent in the command.
|
|
<B><TT>aDigest</TT></B> is the digest argument for the command.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Top">Top</A>(int aMsg, int aNumLines)
|
|
</B></FONT>
|
|
<P>
|
|
Sends the TOP command and returns the status code received from the server.
|
|
If no response is received, the function returns zero.
|
|
<B><TT>aMsg</TT></B> is the message number. <B><TT>aNumLines</TT></B> is
|
|
the number of lines to send.
|
|
<P>
|
|
<FONT COLOR="teal"><B> int <A NAME="Uidl">Uidl</A>() <BR>
|
|
int Uidl(int aMsg) </B></FONT>
|
|
<P>
|
|
Sends the TOP command, with or without a message number, and returns the
|
|
status code received from the server. If no response is received, the function
|
|
returns zero.
|
|
</BODY></HTML>
|