Socket Question

perlsyntax has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Socket Question by Joost (Canon) on Nov 28, 2007 at 23:52 UTC
You don't HAVE to use IO::Socket (or its subclasses). They're just slightly better organized and easier to use than the various low-level build-in functions (bind, connect, listen etc). As other people here noted, if you're using any kind of well-known protocol, chances are high there's a CPAN module that will make your work a lot easier still. "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply]
Re: Socket Question by RaduH (Scribe) on Nov 28, 2007 at 23:42 UTC
Assuming TCP connection to some server (sshd on port 22 in the example below), here's an example: `... my $remoteIP ='a.b.c.d'; my $port = 22; #aiming for sshd - use your own port here my $iaddr = inet_aton($remoteIP) \|\| die("No $remoteIP around"); my $paddr = sockaddr_in($port, $iaddr); my $protocol = getprotobyname('tcp'); socket(SOCK, PF_INET, SOCK_STREAM, $protocol) \|\| die("socket() fai +led: $!"); connect(SOCK, $paddr) \|\| die("connect() failed: $!"); $line = <SOCK>; #read a line print("$line online\n"); #print it close(SOCK); #close socket ...` [download]	[reply] [d/l]
Re: Socket Question by Cubes (Pilgrim) on Nov 28, 2007 at 23:35 UTC
What kind of server? There are pre-built CPAN modules available that will help you connect to a variety of common servers (HTTP, SMTP, FTP, and so on).	[reply]
Socket Question by perlsyntax (Pilgrim) on Nov 28, 2007 at 23:40 UTC
Like any network server it don't matter.:)	[reply]
Re: Socket Question by apl (Monsignor) on Nov 29, 2007 at 02:14 UTC
A Client and a Server have to agree on certain things before they start to communicate with each other. The first is the communications protocol they'll use. (The most common these days is TCP/IP. Ten years ago it was X.25 . IBM wishs the world used SNA, which was popular 20 years ago.) Then you both have to agree how you'll exchange information using that communications protocol. Financial institutions now use something called FIX. The Stock Exchanges used to use proprietary message formats. Then you have to worry about the character set you communicate in... So communications prgramming is very, very specific , very detail-oriented.	[reply]
Re: Socket Question by RaduH (Scribe) on Nov 29, 2007 at 00:30 UTC
For some network servers it "DO" matter ... Much to your surprise, you might discover one day not everyone is using what I suspect you assume to be universal (which I think you think it is TCP/IP). The other questions/comments make sense and my answer is an example assuming TCP ...	[reply]
Re: Socket Question by zentara (Cardinal) on Nov 29, 2007 at 14:34 UTC
Check out the Perl examples at UNO examples ; but as others have said, you will manually need to figure out the protocol for the different server types that you want to connect to. I'm not really a human, but I play one on earth. Cogito ergo sum a bum	[reply]