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instance method

MakeMakefile#have_header

have_header(header, preheaders = nil, opt = "", &b)

# File tmp/rubies/ruby-3.1.3/lib/mkmf.rb, line 1153
def have_header(header, preheaders = nil, opt = "", &b)
  dir_config(header[/.*?(?=\/)|.*?(?=\.)/])
  checking_for header do
    if try_header(cpp_include(preheaders)+cpp_include(header), opt, &b)
      $defs.push(format("-DHAVE_%s", header.tr_cpp))
      true
    else
      false
    end
  end
end

Returns whether or not the given header file can be found on your system. If found, a macro is passed as a preprocessor constant to the compiler using the header file name, in uppercase, prepended with HAVE_.

For example, if have_header('foo.h') returned true, then the HAVE_FOO_H preprocessor macro would be passed to the compiler.

See also #have_func #have_library #have_framework #have_macro also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.0

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