[Geotiff] get tifftag_geoasciiparams string

[Gennady Khokhorin]

Hello, All.

I can not find description about what string TIFFGetField(in, TIFFTAG_GEOASCIIPARAMS, &data);
will be returned. 
I saw somewhere it is a set of multi strings separated by '|' char. Is a whole set terminated by '\0'?
Is it for sure so I can use strlen(data)?
Please, point me which doc or code I should check.

Thanks!
gok