1AC_CHECK_HEADERS([stdbool.h], 2[ 3 AH_TEMPLATE([USE_STDBOOL_H], [whether or not to use <stdbool.h>.]) 4 AC_DEFINE([USE_STDBOOL_H]) 5], 6[ 7 AH_TEMPLATE([bool], [type for 'bool' if <stdbool.h> is missing or broken.]) 8 AH_TEMPLATE([true], [value of 'true' if <stdbool.h> is missing or broken.]) 9 AH_TEMPLATE([false], [value of 'false' if <stdbool.h> is missing or broken.]) 10 AC_DEFINE([true], [1]) 11 AC_DEFINE([false], [0]) 12]) 13