libspopc/doc/manual.txt

libspopc manual

Benoit Rouits <brouits@free.fr> 12/28/2001, 12/12/2008


= Introduction =

libspopc is a pop3 client library written in C and uses BSD-style sockets.
It uses sort of blocking sockets, but with a 15s timeout on read and write.
It is available on all Unices and MS-Windows NT/2000/XP with minor tweaks.
It may also work on MS-Windows 95/98/ME with some tweaks (old versions worked)
libspopc is free software, released under the GNU LGPLv2 License.
It is available on http://herewe.servebeer.com/libspopc/index.html
libspopc offers low-level and high-level methods to acces a pop3 server. To
use low-level API, it is recommended to read RFC 1725 (see doc/rfc/). No
special knowledge is required to use the high-level API.
This manual tells how to use libspopc in both low-level and high-level methods.


= Building libspopc =


== on linux, *BSD (and other unices) ==


=== using the Makefile ===

The given Makefile allows to build libspopc in a simple way, on your terminal:

        $ make
        [...]
        $ su -c "make install"
                or
        $ sudo make install

For the full version of libspopc, you need:

- GNU make (or old standard make, though not tested)
- a c compiler                 (gcc only has been tested)
- a libc                       (glibc and dietlibc have been tested)
- a librt provided with libc   (for libspopc version >= 0.9)
- openssl and libcrypto        (for SSL support)


=== use dietlibc instead of the system's libc ===

- install dietlibc and set the DIET macro to "diet" in the Makefile
- remove -pedantic-errors in CFLAGS


=== disable SSL support ===

- remove -DUSE_SSL from CFLAGS in the Makefile
- remove -lcrypto -lssl from LDFLAGS in the Makefile


=== disable use of semaphores if you do not use threads ===

- remove -D_REENTRANT from CFLAGS in the Makefile
- remove -lrt from LDFLAGS in the Makefile


== on MacOSX ==

libspopc should build easily on MacOSX, using the developer tools (gnu make,
gcc). Please tell me if you succeed to or not.


== on MS-Windows 95/98/ME and NT/XP/2000/2003/Vista ==

Libspopc builds successfuly on these flavours. The main trick is to import
libspopc sources in you IDE and create an appropriate "project" for it.
The archive contains a working project for the dev-cpp IDE (and Makefile.win
that should work for MinGW. This porject/Makefile enables openssl, so you have
to download openssl for win32 if you use them as is.
You also need at last MSVCRT.DLL and WSOCK32.DLL.


== on OpenVMS ==

libspopc builds successfully on OpenVMS. Use the build_libspopc.com in the
vms/ directory to build libspopc with or without SSL suuport. See how to use
this script in the vms_readme.txt documentation file. Note that currently,
the re-entrant code of libspopc is disabled for OpenVMS. If you have troubles
building libspopc, you can install an older binary package provided by Quadratrix. See: http://www.quadratrix.be/opensource.html


= Programming with libspopc =

libspopc provides 2 levels of programmation. One of them allow you to know
nothing about socket programming nor to have read entirely the POP3 RFC.
The second one allow you to deal with sockets and low-level POP3 queries. In
the latter case, you must have read rhe POP3 RFC and know a bit on network
programming. Use the one you prefer, but DO NOT MIX USE OF THE 2 APIs.


== The high-level API (the easy way) ==


=== declarations ===
To use libspopc, you have to include in your main program the libspopc header:

        #include <libspopc.h>

Then, in you main function, declare a popsession* object. You don't need to
know what a popsession consists of, but if you are curious, see libspopc.h.

        popsession* mysession;


=== starting the pop session ===

Since version 0.9, you must call libspopc_init() before starting to use libspopc routines.

        libspopc_init(); /* version >= 0.9 */

Now, to start a pop3 dialog with a pop3 server, use:

        error = popbegin(char* servername, char* user, char* pass, popsession** &mysession);

If no error occurs, popbegin returns a NULL pointer. Else, it returns an error
message and the session is not initialized. When the session is initialized,
popbegin will asks the pop3 server to give him knowledge of how many messages 
are stored, and how many bytes, etc... You can know them by reading the popsession
members with provided macros (see <libspopc.h>).


=== dealing with the pop server ===

Once the session has begun, you can directly ask what is the last mail id:

        int last,total;
        last = mysession->last;
        total = mysession->num;

In the begining of a pop3 session, last and total emails are the same.
An email is accessable through its 'id' (from 1 to last).
Hence, you can ask everything you want on messages:

        for(i=1;i<=last;i++){
                size=popmsgsize(mysession,i);
        /* the size in bytes of message i */

                sig=popmsguid(mysession,i);
        /* the unique signature of message i */

                head=popgethead(mysession,i);
        /* the message header */

                msg=popgetmsg(mysession,i);
        /* the message itself */

                popdelmsg(mysession,i);
        /* deletes the message on server */
        }

You can perform automatic deletion after retrieving a message by asking it to
the session:

        popsetdel(mysession);

or stop it by calling:

        popsetundel(mysession);

Be careful if you use threads, then: avoid using 2 threads on the same session.
If you want to force cancelation of all previous deletions, ask before quit:

        popcancel(mysession);

Deconnection is then made by a call to:

        popend(mysession);

To start a new pop3 session, you will have to use popbegin(...) again.


=== ending with libspopc routines ===

Since version 0.9, you must call libspopc_clean() when you do not want to use
anymore libspopc routines. For example, before your program exits, you will
have to call the following routine:

        libspopc_clean(); /* version >= 0.9 */

There are several other methods to deal with the pop server, see the complete
list in file libspopc.h in section "high-level methods".
See also example poptest2.c in libspopc example sources.


== The low-level API (the hacky way) ==

The low-level API is *another way* to dilog with a pop3 server.
If you choose to use this API, forget about the previous sections.


=== declarations ===

To use libspopc, you have to include in your main program the libspopc header:

        #include <libspopc.h>

Then, in your main function, you have to declare some network-oriented
structures in order to use BSD sockets:

        int mysocket;
        struct hostent myserver;
        struct sockaddr_in myconnection;

and some specific libspopc types:

        int* mylist;
        char** myuidl;

mylist will hold an array of sizes of any messages stored in the pop server.
(int)mylist[0] is a special cell which holds the number of elements in the list.
This list is indexed by the current session's message number.

myuidl will hold an array of unique signatures of messages stored in the pop server.
This list is indexed by the all-time messages ids. This allows you to
keep track of which message you have already read in a previous pop3 session.
(char*)myuidl[0] is a special cell which holds the number of signatures.
You can get it with well known function atoi() declared in <stdlib.h>.


=== connection ===

Since version 0.9, you must call libspopc_init() before starting to use libspopc routines.

        libspopc_init(); /* version >= 0.9 */

Now, you can prepare a pop3 connection:

        mysocket = pop3_prepare(myservername,0,&myconnection,&myserver);

where myservername is a (char*) string holding the internet name of the pop3 server.
pop3_prepare will return -1 if a problem occured.
If no problem occured, you can connect to the pop3 server:

        (char*)message = pop3_connect(mysock,&myconnection);

if message is NULL, the connection failed. Else, check the server's response:

        if(pop3_error(message)){
                printf("%s",message);
                pop3_disconnect(mysock);
        }

As you can see in this sample, a call to pop3_disconnect will disconnect from
the server if connection failed, and free all data structures allocated by
pop3_prepare and pop3connect.


=== dealing with the pop server ===

For a complete description of pop3 methods, see <libspopc.h> in section 'pop3 queries'.
It is recommended to read RFC 1725 also, because of some 
particularities of the pop3 protocol. Else, here are some tricks about them:


==== statistics ====

        char* data;
        data = pop3_stat(mysock);
        if(pop3_error(data)){
                printf("%s",data);
        }else{
                printf("stat: %d mail(s)\n",stat2num(data));
                printf("stat: %d bytes\n",stat2bytes(data));
        }
        free(data);


==== listing ====

        int* mylist
        data = pop3_list(mysock,0); /* 0 means all messages */
        if(pop3_error(data)){
                printf("%s",data);
        }else{
                mylist=list2array(data);
        }
        free(data);
        for(i=1;i<=mylist[0];i++){
                printf("msg %d is of %d bytes\n",i,mylist[i]);
        }
        free(mylist);


==== retrieving ====

        char* mymessage;
        data = pop3_retr(mysock,i);
        if(pop3_error(data)){
                printf("%s",data);
        }else{
                mymessage=retr2msg(data);
                printf("message %d:\n%s",i,mymessage);
                free(mymessage);
        }
        free(data);


==== disconnecting ====

        data = pop3_quit(mysock);
        printf("server says:%s",data);
        pop3_disconnect(mysock);


=== ending with libspopc routines ===

Since version 0.9, you must call libspopc_clean() when you do not want to use
anymore libspopc routines. For example, before your program exits, you will
have to call the following routine:

        libspopc_clean(); /* version >= 0.9 */

There are several other pop3 queries that you can see in <libspopc.h> and
explained in RFC1725. For an example, see examples/poptest1.c in libspopc 
example sources.


== Download, Contribute... ==


=== Download ===
libspopc is always available at 
        http://herewe.servebeer.com/libspopc/index.html

The SVN development tree is freely accessible in read-only anonymous mode.

feedback, patches, questions and bug report can be sent to <brouits@free.fr>


== Authors ==
- Original and main author: Benoît Rouits <brouits@free.fr>
- Main contributors: see AUTHORS file in the libspopc sources.
- Contributions: see ChangeLog file in the libspopc sources.

1	libspopc manual
2
3	Benoit Rouits <brouits@free.fr> 12/28/2001, 12/12/2008
4
5
6	= Introduction =
7
8	libspopc is a pop3 client library written in C and uses BSD-style sockets.
9	It uses sort of blocking sockets, but with a 15s timeout on read and write.
10	It is available on all Unices and MS-Windows NT/2000/XP with minor tweaks.
11	It may also work on MS-Windows 95/98/ME with some tweaks (old versions worked)
12	libspopc is free software, released under the GNU LGPLv2 License.
13	It is available on http://herewe.servebeer.com/libspopc/index.html
14	libspopc offers low-level and high-level methods to acces a pop3 server. To
15	use low-level API, it is recommended to read RFC 1725 (see doc/rfc/). No
16	special knowledge is required to use the high-level API.
17	This manual tells how to use libspopc in both low-level and high-level methods.
18
19
20	= Building libspopc =
21
22
23	== on linux, *BSD (and other unices) ==
24
25
26	=== using the Makefile ===
27
28	The given Makefile allows to build libspopc in a simple way, on your terminal:
29
30	$ make
31	[...]
32	$ su -c "make install"
33	or
34	$ sudo make install
35
36	For the full version of libspopc, you need:
37
38	- GNU make (or old standard make, though not tested)
39	- a c compiler (gcc only has been tested)
40	- a libc (glibc and dietlibc have been tested)
41	- a librt provided with libc (for libspopc version >= 0.9)
42	- openssl and libcrypto (for SSL support)
43
44
45	=== use dietlibc instead of the system's libc ===
46
47	- install dietlibc and set the DIET macro to "diet" in the Makefile
48	- remove -pedantic-errors in CFLAGS
49
50
51	=== disable SSL support ===
52
53	- remove -DUSE_SSL from CFLAGS in the Makefile
54	- remove -lcrypto -lssl from LDFLAGS in the Makefile
55
56
57	=== disable use of semaphores if you do not use threads ===
58
59	- remove -D_REENTRANT from CFLAGS in the Makefile
60	- remove -lrt from LDFLAGS in the Makefile
61
62
63	== on MacOSX ==
64
65	libspopc should build easily on MacOSX, using the developer tools (gnu make,
66	gcc). Please tell me if you succeed to or not.
67
68
69	== on MS-Windows 95/98/ME and NT/XP/2000/2003/Vista ==
70
71	Libspopc builds successfuly on these flavours. The main trick is to import
72	libspopc sources in you IDE and create an appropriate "project" for it.
73	The archive contains a working project for the dev-cpp IDE (and Makefile.win
74	that should work for MinGW. This porject/Makefile enables openssl, so you have
75	to download openssl for win32 if you use them as is.
76	You also need at last MSVCRT.DLL and WSOCK32.DLL.
77
78
79	== on OpenVMS ==
80
81	libspopc builds successfully on OpenVMS. Use the build_libspopc.com in the
82	vms/ directory to build libspopc with or without SSL suuport. See how to use
83	this script in the vms_readme.txt documentation file. Note that currently,
84	the re-entrant code of libspopc is disabled for OpenVMS. If you have troubles
85	building libspopc, you can install an older binary package provided by Quadratrix. See: http://www.quadratrix.be/opensource.html
86
87
88	= Programming with libspopc =
89
90	libspopc provides 2 levels of programmation. One of them allow you to know
91	nothing about socket programming nor to have read entirely the POP3 RFC.
92	The second one allow you to deal with sockets and low-level POP3 queries. In
93	the latter case, you must have read rhe POP3 RFC and know a bit on network
94	programming. Use the one you prefer, but DO NOT MIX USE OF THE 2 APIs.
95
96
97	== The high-level API (the easy way) ==
98
99
100	=== declarations ===
101	To use libspopc, you have to include in your main program the libspopc header:
102
103	#include <libspopc.h>
104
105	Then, in you main function, declare a popsession* object. You don't need to
106	know what a popsession consists of, but if you are curious, see libspopc.h.
107
108	popsession* mysession;
109
110
111	=== starting the pop session ===
112
113	Since version 0.9, you must call libspopc_init() before starting to use libspopc routines.
114
115	libspopc_init(); /* version >= 0.9 */
116
117	Now, to start a pop3 dialog with a pop3 server, use:
118
119	error = popbegin(char* servername, char* user, char* pass, popsession** &mysession);
120
121	If no error occurs, popbegin returns a NULL pointer. Else, it returns an error
122	message and the session is not initialized. When the session is initialized,
123	popbegin will asks the pop3 server to give him knowledge of how many messages
124	are stored, and how many bytes, etc... You can know them by reading the popsession
125	members with provided macros (see <libspopc.h>).
126
127
128	=== dealing with the pop server ===
129
130	Once the session has begun, you can directly ask what is the last mail id:
131
132	int last,total;
133	last = mysession->last;
134	total = mysession->num;
135
136	In the begining of a pop3 session, last and total emails are the same.
137	An email is accessable through its 'id' (from 1 to last).
138	Hence, you can ask everything you want on messages:
139
140	for(i=1;i<=last;i++){
141	size=popmsgsize(mysession,i);
142	/* the size in bytes of message i */
143
144	sig=popmsguid(mysession,i);
145	/* the unique signature of message i */
146
147	head=popgethead(mysession,i);
148	/* the message header */
149
150	msg=popgetmsg(mysession,i);
151	/* the message itself */
152
153	popdelmsg(mysession,i);
154	/* deletes the message on server */
155	}
156
157	You can perform automatic deletion after retrieving a message by asking it to
158	the session:
159
160	popsetdel(mysession);
161
162	or stop it by calling:
163
164	popsetundel(mysession);
165
166	Be careful if you use threads, then: avoid using 2 threads on the same session.
167	If you want to force cancelation of all previous deletions, ask before quit:
168
169	popcancel(mysession);
170
171	Deconnection is then made by a call to:
172
173	popend(mysession);
174
175	To start a new pop3 session, you will have to use popbegin(...) again.
176
177
178	=== ending with libspopc routines ===
179
180	Since version 0.9, you must call libspopc_clean() when you do not want to use
181	anymore libspopc routines. For example, before your program exits, you will
182	have to call the following routine:
183
184	libspopc_clean(); /* version >= 0.9 */
185
186	There are several other methods to deal with the pop server, see the complete
187	list in file libspopc.h in section "high-level methods".
188	See also example poptest2.c in libspopc example sources.
189
190
191	== The low-level API (the hacky way) ==
192
193	The low-level API is another way to dilog with a pop3 server.
194	If you choose to use this API, forget about the previous sections.
195
196
197	=== declarations ===
198
199	To use libspopc, you have to include in your main program the libspopc header:
200
201	#include <libspopc.h>
202
203	Then, in your main function, you have to declare some network-oriented
204	structures in order to use BSD sockets:
205
206	int mysocket;
207	struct hostent myserver;
208	struct sockaddr_in myconnection;
209
210	and some specific libspopc types:
211
212	int* mylist;
213	char** myuidl;
214
215	mylist will hold an array of sizes of any messages stored in the pop server.
216	(int)mylist[0] is a special cell which holds the number of elements in the list.
217	This list is indexed by the current session's message number.
218
219	myuidl will hold an array of unique signatures of messages stored in the pop server.
220	This list is indexed by the all-time messages ids. This allows you to
221	keep track of which message you have already read in a previous pop3 session.
222	(char*)myuidl[0] is a special cell which holds the number of signatures.
223	You can get it with well known function atoi() declared in <stdlib.h>.
224
225
226	=== connection ===
227
228	Since version 0.9, you must call libspopc_init() before starting to use libspopc routines.
229
230	libspopc_init(); /* version >= 0.9 */
231
232	Now, you can prepare a pop3 connection:
233
234	mysocket = pop3_prepare(myservername,0,&myconnection,&myserver);
235
236	where myservername is a (char*) string holding the internet name of the pop3 server.
237	pop3_prepare will return -1 if a problem occured.
238	If no problem occured, you can connect to the pop3 server:
239
240	(char*)message = pop3_connect(mysock,&myconnection);
241
242	if message is NULL, the connection failed. Else, check the server's response:
243
244	if(pop3_error(message)){
245	printf("%s",message);
246	pop3_disconnect(mysock);
247	}
248
249	As you can see in this sample, a call to pop3_disconnect will disconnect from
250	the server if connection failed, and free all data structures allocated by
251	pop3_prepare and pop3connect.
252
253
254	=== dealing with the pop server ===
255
256	For a complete description of pop3 methods, see <libspopc.h> in section 'pop3 queries'.
257	It is recommended to read RFC 1725 also, because of some
258	particularities of the pop3 protocol. Else, here are some tricks about them:
259
260
261	==== statistics ====
262
263	char* data;
264	data = pop3_stat(mysock);
265	if(pop3_error(data)){
266	printf("%s",data);
267	}else{
268	printf("stat: %d mail(s)\n",stat2num(data));
269	printf("stat: %d bytes\n",stat2bytes(data));
270	}
271	free(data);
272
273
274	==== listing ====
275
276	int* mylist
277	data = pop3_list(mysock,0); /* 0 means all messages */
278	if(pop3_error(data)){
279	printf("%s",data);
280	}else{
281	mylist=list2array(data);
282	}
283	free(data);
284	for(i=1;i<=mylist[0];i++){
285	printf("msg %d is of %d bytes\n",i,mylist[i]);
286	}
287	free(mylist);
288
289
290	==== retrieving ====
291
292	char* mymessage;
293	data = pop3_retr(mysock,i);
294	if(pop3_error(data)){
295	printf("%s",data);
296	}else{
297	mymessage=retr2msg(data);
298	printf("message %d:\n%s",i,mymessage);
299	free(mymessage);
300	}
301	free(data);
302
303
304	==== disconnecting ====
305
306	data = pop3_quit(mysock);
307	printf("server says:%s",data);
308	pop3_disconnect(mysock);
309
310
311	=== ending with libspopc routines ===
312
313	Since version 0.9, you must call libspopc_clean() when you do not want to use
314	anymore libspopc routines. For example, before your program exits, you will
315	have to call the following routine:
316
317	libspopc_clean(); /* version >= 0.9 */
318
319	There are several other pop3 queries that you can see in <libspopc.h> and
320	explained in RFC1725. For an example, see examples/poptest1.c in libspopc
321	example sources.
322
323
324	== Download, Contribute... ==
325
326
327	=== Download ===
328	libspopc is always available at
329	http://herewe.servebeer.com/libspopc/index.html
330
331	The SVN development tree is freely accessible in read-only anonymous mode.
332
333	feedback, patches, questions and bug report can be sent to <brouits@free.fr>
334
335
336	== Authors ==
337	- Original and main author: Benoît Rouits <brouits@free.fr>
338	- Main contributors: see AUTHORS file in the libspopc sources.
339	- Contributions: see ChangeLog file in the libspopc sources.
340