+dnl Checks that the functions listed in FUNCTIONS exist in the headers and the
+dnl libs. For each function, if it is found then defines 'HAVE_FUNCTION' and
+dnl executes ACTION-IF-FOUND, otherwise executes ACTION-IF-NOT-FOUND.
+dnl
+dnl The code from EXTRA-DEFINES-AND-INCLUDES is inserted into the test before
+dnl the default headers are included, and EXTRA-TEST-CODE is inserted into
+dnl the main() function after the default test for existence.
+dnl
+dnl Examples:
+dnl # the simple case
+dnl WX_CHECK_FUNCS(stat)
+dnl # use break to finish the loop early
+dnl WX_CHECK_FUNCS(mkstemp mktemp, break)
+dnl # extra defines
+dnl WX_CHECK_FUNCS(strtok_r, [], [], [#define _RREENTRANT])
+dnl # extra includes
+dnl WX_CHECK_FUNCS(swprintf, [], [], [#include <wchar.h>])
+dnl # checking the signature with extra test code
+dnl WX_CHECK_FUNCS(gettimeofday, [], [], [#include <sys/time.h>]
+dnl [struct timeval tv; struct timezone tz; gettimeofday(&tv, &tz)])