[sac-dev] SAC format questions

[Chad]

Howdy,

I recently put together a simple SAC to miniSEED converter (a bit of wheel
reinventing).  My sac2mseed has some nice features: format and byte order
autodetection, autoscaling of floats to ints when needed.  I had a few
questions regarding the format:

- Most SAC reading code out there works with version '6' of the header, how
common are other versions of the header, does 6 cover the vast majority?

- Autodetection of format tests the first 4 bytes in a file, if they're spaces
alphanumeric format is assumed.  Is this test valid?

- Besides little/big endian binary with 32-bit floats and alphanumeric are
there any other format variants in the wild?

Any comments would be appreciated.

cheers,
Chad