SMTP

Ellops · 12-31-2005, 05:03 AM

Hi codrades.

I've undertaken a project in university, that(in a part) has to do with sending e-mail.

The technical part of implementation is not much of concern right now. I just want play a bit
with the smpt prot, getting aquanted with it.

Does anybody knows where can I find a spefication file on smtp protocol?

I dont mean the rfc's, available.

For example:
I wrote a simple prog in C, that works with the same logic as telneting an SMTP server.It connects to a spcific server and does nothing until it gets a 220 reply. Walking through existing API's (quit creepy) I found that the reply should be read as a LONG number...
Guess what... it didn't work! It connects but the reply was something scrappy...

Obviously I missing something... Thats why I need documentation on technical stuff like that (can I name it SMTP specification file? )

My ignorance don't let me be more specific, Im quite lost...

If anybody has gone through the same, please help a bit. Even a hint or a specific "keyword" will do.. (I know, some things cannot be explained, through forums.)

Thanx.

dmail · 12-31-2005, 06:26 AM

I think these are the two you need to look at rfc821 and the updated rfc2821.
http://www.faqs.org/rfcs/rfc821.html
http://www.faqs.org/rfcs/rfc2821.html

<edit> I just noticed you said

Quote:

I dont mean the rfc's, available.

So what is it your are looking for then?

foo_bar_foo · 12-31-2005, 10:11 PM

yea i can't figure out what you are saying either
i don't know what you mean reply is a long number ?
it replys a string and you have to use atoi() to get the number from the string
a snipit of code from a smtp class i wrote might help
FILE *rfp; // is the recieve socket

Code:

int  mySMTP::get_response()
{
    char buf[BUFSIZ];
    char nCode[4]={0};
    while (fgets(buf, sizeof(buf), rfp)) {
        buf[strlen(buf)-1] = 0;
        printf("%s --> %s\n", host, buf);
        if (!isdigit(buf[0]) || buf[0] > '3') {
	  //exit(1);
          return 1;
        }
        if (buf[4] != '-')
            break;
    }
    strncpy(nCode, buf, 3);
    nCode[3] = '\0';
    return (atoi(nCode));
}

paulsm4 · 12-31-2005, 11:43 PM

The heart of SMTP (and quite likely the gist of the exercise with "telnet" you mentioned) is the *protocol*. Not the networking, not any hypothetical API.

And it happens to be a *text* protocol (having nothing directly to do with "long's" or with C programs).

I agree with the previous two poster's: there's absolutely no better place to start out than with the RFC's:

Quote:

I think these are the two you need to look at rfc821 and the updated rfc2821.
http://www.faqs.org/rfcs/rfc821.html
http://www.faqs.org/rfcs/rfc2821.html

Ellops · 01-02-2006, 06:04 AM

Quote:

Originally Posted by paulsm4

And it happens to be a *text* protocol (having nothing directly to do with "long's" or with C programs).

oh, say that again...!

Thanks alot guys,all of u, I was lookin in wrong places... I'd already read the rfc's, but things were not cleared in my mind.
Yes, now works fine.

Many thanks!

vskgopu · 05-05-2006, 03:18 AM

Which is best for implementing SMTP relay servers in unix.. fork or pthread ?

vskgopu · 05-05-2006, 03:19 AM

Which is best for implementing SMTP relay servers in unix.. fork or pthread ?