Had a look at the Programmer's Manual (April 2011, doc version 2.4) appendix G (compiler defines)

Saw
ENDIAN_LITTLE
ENDIAN_BIG

Did not see
FPC_LITTLE_ENDIAN
FPC_BIG_ENDIAN

Should that be added?

Also, I'm sure there must be functions to convert endianness - at least
network byte order (big endian) to host order.
I found e.g. Synapse synsock:
  function ntohs(netshort: word): word;
  function ntohl(netlong: longword): longword;
  function htons(hostshort: word): word;
  function htonl(hostlong: longword): longword;

Are there an equivalent RTL/FCL functions?

Thanks,
Reinier

They are in FPC's sockets unit.

Regards,
Sven

In our previous episode, Reinier Olislagers said:

Yes, but don't use them.

There are independent endian routines in system. Search for swapendian and BEtoN, NtoBE etc.

Do not abuse network routines for non network usage.

Marco van de Voort wrote

In our previous episode, Reinier Olislagers said: > > Also, I'm sure there must be functions to convert endianness - at least > network byte order (big endian) to host order.

<snip>

Thanks.

Do not abuse network routines for non network usage.

I hear & obey ;)
Updated the wiki:
http://wiki.lazarus.freepascal.org/Writing_portable_code_regarding_the_processor_architecture#Changing_Endianness

Thanks,

Reinier