[SAC-HELP] Header seems byte-swapped -- byte-swap file and retry

[Shahar Kadmiel שחר קדמיאל]

I have some SAC files produced by a code running on Linux (CentOS)  
with Xeon processors and when I try to read them from within SAC I get  
this message:

ERROR 1318: Header in disk file is out of date: (name of file)
Header version number is incorrect.
Header seems byte-swapped -- byte-swap file and retry

I am using MacSAC which I thought doesn't care if the file is little  
or big endian.
I cannot find the sacswap tool that apparently is distributed with  
MacSAC.

The same code running on SUN machines produces SAC files which I have  
no problem reading.

What to do?