Hi Helmut, thank you for the bug report. I think the reason for the floating point version numbering is that cfitsio has a funny version numbering that really treats (treated?) the version number as float (normally with two fractional digits, however). From the changes.txt:
Version 3.20 - 31 August 2009 Version 3.181 (BETA) - 12 May 2009 Version 3.18 (BETA) - 10 April 2009 That *may* have canged with the introduction of CFITSIO_MAJOR and CFITSIO_MINOR in version 3.26; however traditionally many people still refer to the traditional floating point approach -- also the Debian package uses this. I will however contact (CPL) upstream with your suggestion. Best regards Ole