dfits - display FITS file header information

dfits  displays  FITS  header  informations on stdout. Header information can be found in the main header
       only (default), in extensions, or in both.  See the -x option below.   dfits  accepts  multi-file  input.
       'dfits-'  expects  single  file  data coming from stdin.  dfits also accepts now 'HDR' files. These are
       identified from the fact that they contain a line feed in one of the 80 first characters.

       Files shall all comply with FITS format

                                                   30 Mar 2000                                          dfits(1)

       dfits - display FITS file header information

-xxtnum
              Specifies the extension to print out. Extensions are numbered starting from 1. If this  option  is
              not  specified,  only  the  main header is printed out. If this option specifies an extension that
              does not exist, nothing is printed out.
              Specify 0 as extension number to get a print of the main header plus all extension headers.

       Examples :
       dfits *.fits
       dfits *.fits | grep NAXIS3
       gzip -d < star.fits.gz | dfits- | more
       dfits -x 0 *.fits
       dfits -x 3 *.fits

fitsort can be combined with dfits output to sort out keyword values of a group of FITS files.

dfits [-x xtnum] <list>
       dfits [-x xtnum] -