/usr/lib/libhdf4.settings is in libhdf4-alt-dev 4.2.13-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | 	    SUMMARY OF THE HDF4 CONFIGURATION
	    =================================
General Information:
-------------------
		   HDF4 Version: 4.2.13
		 Configure mode: production
		      Libraries: 
	     Installation point: /usr
Compiling Options:
------------------
               Compilation Mode: production
                     C compiler: /usr/bin/gcc
                         CFLAGS:  -O2 -fdebug-prefix-map=/build/libhdf4-7EZHsI/libhdf4-4.2.13=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -O3 -fomit-frame-pointer
                       CPPFLAGS: -Wdate-time -D_FORTIFY_SOURCE=2 -DBIG_LONGS -DSWAP 
               Shared Libraries: yes
               Static Libraries: yes
  Statically Linked Executables: no
                        LDFLAGS: -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-z,now
 	 	Extra libraries: -ljpeg -lz 
 		       Archiver: ar
 		 	 Ranlib: ranlib
Languages:
----------
                        Fortran: no
                           Java: no
Features:
---------
               SZIP compression: enabled with decoder only
   Support for netCDF API 2.3.2: no
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