Defines the sockets and protocols used for Internet services.
The /etc/services file contains information about the known services used in the DARPA Internet network. Each service is listed on a single line corresponding to the form:
ServiceName PortNumber/ProtocolName Aliases
These fields contain the following information:
| Item | Description | 
|---|---|
| ServiceName | Specifies an official Internet service name. | 
| PortNumber | Specifies the socket port number used for the service. | 
| ProtocolName | Specifies the transport protocol used for the service. | 
| Aliases | Specifies a list of unofficial service names. | 
Items on a line are separated by spaces or tabs. Comments begin with a # (pound sign) and continue until the end of the line.
If you edit the /etc/services file, run the refresh -s inetd or kill -1 InetdPID command to inform the inetd daemon of the changes.
Entries in the services file for the inetd internal services may look like this:
echo          7/tcp
echo          7/udp
discard       9/tcp      sink null
discard       9/udp      sink null
daytime      13/tcp
daytime      13/udp
chargen      19/tcp      ttytst source
chargen      19/udp      ttytst source
ftp          21/tcp
time         37/tcp      timeserver
time         37/udp      timeserver