method

have_var

ruby latest stable - Class: Object

have_var(var, headers = nil, &b)

public

Returns whether or not the variable var can be found in the common header files, or within any headers that you provide. If found, a macro is passed as a preprocessor constant to the compiler using the variable name, in uppercase, prepended with ‘HAVE_’.

For example, if have_var(‘foo’) returned true, then the HAVE_FOO preprocessor macro would be passed to the compiler.

# File lib/mkmf.rb, line 911
def have_var(var, headers = nil, &b)
  checking_for checking_message(var, headers) do
    if try_var(var, headers, &b)
      $defs.push(format("-DHAVE_%s", var.tr_cpp))
      true
    else
      false
    end
  end
end

have_var

Method deprecated or moved

Related methods