mkc_check_header - detects presense of header file.

       Aleksey Cheusov <vle@gmx.net>

                                                  Mar 30, 2019                               MKC_CHECK_HEADER(1)

       #include <header1.h>
        ...
       #include <headerN.h>
       int __fake_variable;

mkc_check_header  detects presense of header file.  As a result it prints either 1 (true) or 0 (false) to
       stdout.  headers may be either a single header file or a list of headers separated  by  comma.   In  this
       case all mentioned headers are put into a single .c file and ${CC} is run.  By default $CC-c is used for
       checking.   By  default,  temporary  and  cache files _mkc_header_lheader_h.{c,err,res} are created under
       MKC_CACHEDIR directory. Here, lheader_h is the last header from comma-separated list headers.

CC     Compiler. By default cc is used.

       CPPFLAGS,CFLAGS
              Options passed to the compiler.

       MKC_VERBOSE
              If set to 1, verbose messages are output to stderr.

       MKC_SHOW_CACHED
              If set to 1 and MKC_VERBOSE is set to 1, cached results are output to stderr.

       MKC_CACHEDIR
              Directory where temporary and cache files are created.  If unset they are  created  in  a  current
              directory.

       MKC_NOCACHE
              All results are cached unless MKC_NOCACHE variable is set to 1.

       MKC_DELETE_TMPFILES
              If set to 1, temporary files are removed.

          mkc_check_header stdint.h
          mkc_check_header getopt.h
          mkc_check_header sys/types.h,sys/stat.h,fts.h

       mkc_check_header - detects presense of header file.

-h     Display help message.

       -e     Use $CC-E for checking instead of $CC-c.

       -d     Delete cache file.

mkc_check_header[OPTIONS]<headers>