Source: http://linuxsat-support.com/cccam-support-tutorials/4907-cline-setting.html

Syntax : C: <hostname> <port> <username> <password> <wantemus> { caid:id:uphops, caid:id:uphops, … }

In a C line we can have :

1. Instructions where to look for a server <hostname>
2. Which port that server is using <port>
3. Username to connect to that server <username>
4. Password to connect to that server <password>
5. If you like to recieve Emulator shares from keys <wantemus> (i recommend using “no” here)
6. Limiting what to get from that particular server { caid:id:uphops, caid:id:uphops, … }

Examples

Basic C line that most users will use :
C: server.noip.com 12000 username password

C line that is more appropriate if you do not want to recieve key Emulators:
C: server.noip.com 12000 username password no

C line that is more appropriate if you want to recieve key Emulators (NOT  recommended) :
C: server.noip.com 12000 username password yes

Cline that will limit to receive all shares that are only up to 2 hops away (Recommended!!):
C: server.noip.com 12000 username password no { 0:0:2 }

Cline that will get all shares but does not get a specific provider:
C: server.noip.com 12000 username password no { 0:0:2, 093b:0 }

Cline that will get all shares but does not get specific providers:
C: server.noip.com 12000 username password no { 0:0:2, 100:3, 100:4, 100:5, 100:9, 100:A, 100:c }