Easy question about ports

Sorry for this foolish question.

Port number (/etc/services) depend on architecture or OS?

I only use Linux on pentium machine.
I never tried `port' on other OSes or other machines. :)

You're talking about two completely different ports :)

Ports in /etc/services are talking about TCP/IP (UDP) ports where an IP address and a port combined make a socket.

When talking about porting an application between different OSes or architectures it has nothing to do with what's in /etc/services on Linux.

I may not understand you correctly.
I meant...
inetd, a super server, is listening for port access.
For example ftp must access via port number 21.
If I switch to others such as SunOS on SPARC machine.
I question whether ftp still access via port number 21 or not.
If not, it depends on architectural or OS?

Thanks,

Port numbers are part of TCP/IP and has nothing to do with the architecture. Every OS has an implementation of TCP/IP based on the TCP/IP standard so they all have the same port numbers unless the admin manually changes which port a certain service listens on.

Thanks, that's what I want to know. :)