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 NT/XP/2000/2003/Vista ==

It has been reported that 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 an Makefile.win for
the dev-cpp IDE.


== on MS-Windows 95/98/ME ==

Early versions of libspopc have been successfully built upon these flavours.
As far as i know, you must have MSVCRT.DLL and WSOCK32.DLL... The latest
version of libspopc should do the same. The archive contains a working project
and Makefile.win for the dev-cpp IDE.


== 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 NT/XP/2000/2003/Vista ==
70
71	It has been reported that libspopc builds successfuly on these flavours. The
72	main trick is to import libspopc sources in you IDE and create an appropriate
73	"project" for it. The archive contains a working project an Makefile.win for
74	the dev-cpp IDE.
75
76
77	== on MS-Windows 95/98/ME ==
78
79	Early versions of libspopc have been successfully built upon these flavours.
80	As far as i know, you must have MSVCRT.DLL and WSOCK32.DLL... The latest
81	version of libspopc should do the same. The archive contains a working project
82	and Makefile.win for the dev-cpp IDE.
83
84
85	== on OpenVMS ==
86
87	libspopc builds successfully on OpenVMS. Use the build_libspopc.com in the
88	vms/ directory to build libspopc with or without SSL suuport. See how to use
89	this script in the vms_readme.txt documentation file. Note that currently,
90	the re-entrant code of libspopc is disabled for OpenVMS. If you have troubles
91	building libspopc, you can install an older binary package provided by Quadratrix. See: http://www.quadratrix.be/opensource.html
92
93
94	= Programming with libspopc =
95
96	libspopc provides 2 levels of programmation. One of them allow you to know
97	nothing about socket programming nor to have read entirely the POP3 RFC.
98	The second one allow you to deal with sockets and low-level POP3 queries. In
99	the latter case, you must have read rhe POP3 RFC and know a bit on network
100	programming. Use the one you prefer, but DO NOT MIX USE OF THE 2 APIs.
101
102
103	== The high-level API (the easy way) ==
104
105
106	=== declarations ===
107	To use libspopc, you have to include in your main program the libspopc header:
108
109	#include <libspopc.h>
110
111	Then, in you main function, declare a popsession* object. You don't need to
112	know what a popsession consists of, but if you are curious, see libspopc.h.
113
114	popsession* mysession;
115
116
117	=== starting the pop session ===
118
119	Since version 0.9, you must call libspopc_init() before starting to use libspopc routines.
120
121	libspopc_init(); /* version >= 0.9 */
122
123	Now, to start a pop3 dialog with a pop3 server, use:
124
125	error = popbegin(char* servername, char* user, char* pass, popsession** &mysession);
126
127	If no error occurs, popbegin returns a NULL pointer. Else, it returns an error
128	message and the session is not initialized. When the session is initialized,
129	popbegin will asks the pop3 server to give him knowledge of how many messages
130	are stored, and how many bytes, etc... You can know them by reading the popsession
131	members with provided macros (see <libspopc.h>).
132
133
134	=== dealing with the pop server ===
135
136	Once the session has begun, you can directly ask what is the last mail id:
137
138	int last,total;
139	last = mysession->last;
140	total = mysession->num;
141
142	In the begining of a pop3 session, last and total emails are the same.
143	An email is accessable through its 'id' (from 1 to last).
144	Hence, you can ask everything you want on messages:
145
146	for(i=1;i<=last;i++){
147	size=popmsgsize(mysession,i);
148	/* the size in bytes of message i */
149
150	sig=popmsguid(mysession,i);
151	/* the unique signature of message i */
152
153	head=popgethead(mysession,i);
154	/* the message header */
155
156	msg=popgetmsg(mysession,i);
157	/* the message itself */
158
159	popdelmsg(mysession,i);
160	/* deletes the message on server */
161	}
162
163	You can perform automatic deletion after retrieving a message by asking it to
164	the session:
165
166	popsetdel(mysession);
167
168	or stop it by calling:
169
170	popsetundel(mysession);
171
172	Be careful if you use threads, then: avoid using 2 threads on the same session.
173	If you want to force cancelation of all previous deletions, ask before quit:
174
175	popcancel(mysession);
176
177	Deconnection is then made by a call to:
178
179	popend(mysession);
180
181	To start a new pop3 session, you will have to use popbegin(...) again.
182
183
184	=== ending with libspopc routines ===
185
186	Since version 0.9, you must call libspopc_clean() when you do not want to use
187	anymore libspopc routines. For example, before your program exits, you will
188	have to call the following routine:
189
190	libspopc_clean(); /* version >= 0.9 */
191
192	There are several other methods to deal with the pop server, see the complete
193	list in file libspopc.h in section "high-level methods".
194	See also example poptest2.c in libspopc example sources.
195
196
197	== The low-level API (the hacky way) ==
198
199	The low-level API is another way to dilog with a pop3 server.
200	If you choose to use this API, forget about the previous sections.
201
202
203	=== declarations ===
204
205	To use libspopc, you have to include in your main program the libspopc header:
206
207	#include <libspopc.h>
208
209	Then, in your main function, you have to declare some network-oriented
210	structures in order to use BSD sockets:
211
212	int mysocket;
213	struct hostent myserver;
214	struct sockaddr_in myconnection;
215
216	and some specific libspopc types:
217
218	int* mylist;
219	char** myuidl;
220
221	mylist will hold an array of sizes of any messages stored in the pop server.
222	(int)mylist[0] is a special cell which holds the number of elements in the list.
223	This list is indexed by the current session's message number.
224
225	myuidl will hold an array of unique signatures of messages stored in the pop server.
226	This list is indexed by the all-time messages ids. This allows you to
227	keep track of which message you have already read in a previous pop3 session.
228	(char*)myuidl[0] is a special cell which holds the number of signatures.
229	You can get it with well known function atoi() declared in <stdlib.h>.
230
231
232	=== connection ===
233
234	Since version 0.9, you must call libspopc_init() before starting to use libspopc routines.
235
236	libspopc_init(); /* version >= 0.9 */
237
238	Now, you can prepare a pop3 connection:
239
240	mysocket = pop3_prepare(myservername,0,&myconnection,&myserver);
241
242	where myservername is a (char*) string holding the internet name of the pop3 server.
243	pop3_prepare will return -1 if a problem occured.
244	If no problem occured, you can connect to the pop3 server:
245
246	(char*)message = pop3_connect(mysock,&myconnection);
247
248	if message is NULL, the connection failed. Else, check the server's response:
249
250	if(pop3_error(message)){
251	printf("%s",message);
252	pop3_disconnect(mysock);
253	}
254
255	As you can see in this sample, a call to pop3_disconnect will disconnect from
256	the server if connection failed, and free all data structures allocated by
257	pop3_prepare and pop3connect.
258
259
260	=== dealing with the pop server ===
261
262	For a complete description of pop3 methods, see <libspopc.h> in section 'pop3 queries'.
263	It is recommended to read RFC 1725 also, because of some
264	particularities of the pop3 protocol. Else, here are some tricks about them:
265
266
267	==== statistics ====
268
269	char* data;
270	data = pop3_stat(mysock);
271	if(pop3_error(data)){
272	printf("%s",data);
273	}else{
274	printf("stat: %d mail(s)\n",stat2num(data));
275	printf("stat: %d bytes\n",stat2bytes(data));
276	}
277	free(data);
278
279
280	==== listing ====
281
282	int* mylist
283	data = pop3_list(mysock,0); /* 0 means all messages */
284	if(pop3_error(data)){
285	printf("%s",data);
286	}else{
287	mylist=list2array(data);
288	}
289	free(data);
290	for(i=1;i<=mylist[0];i++){
291	printf("msg %d is of %d bytes\n",i,mylist[i]);
292	}
293	free(mylist);
294
295
296	==== retrieving ====
297
298	char* mymessage;
299	data = pop3_retr(mysock,i);
300	if(pop3_error(data)){
301	printf("%s",data);
302	}else{
303	mymessage=retr2msg(data);
304	printf("message %d:\n%s",i,mymessage);
305	free(mymessage);
306	}
307	free(data);
308
309
310	==== disconnecting ====
311
312	data = pop3_quit(mysock);
313	printf("server says:%s",data);
314	pop3_disconnect(mysock);
315
316
317	=== ending with libspopc routines ===
318
319	Since version 0.9, you must call libspopc_clean() when you do not want to use
320	anymore libspopc routines. For example, before your program exits, you will
321	have to call the following routine:
322
323	libspopc_clean(); /* version >= 0.9 */
324
325	There are several other pop3 queries that you can see in <libspopc.h> and
326	explained in RFC1725. For an example, see examples/poptest1.c in libspopc
327	example sources.
328
329
330	== Download, Contribute... ==
331
332
333	=== Download ===
334	libspopc is always available at
335	http://herewe.servebeer.com/libspopc/index.html
336
337	The SVN development tree is freely accessible in read-only anonymous mode.
338
339	feedback, patches, questions and bug report can be sent to <brouits@free.fr>
340
341
342	== Authors ==
343	- Original and main author: Benoît Rouits <brouits@free.fr>
344	- Main contributors: see AUTHORS file in the libspopc sources.
345	- Contributions: see ChangeLog file in the libspopc sources.
346