CHECK_FUNCTION_EXISTS(getdtablesize HAVE_GETDTABLESIZE)
CHECK_FUNCTION_EXISTS(sysconf HAVE_SYSCONF)
CHECK_FUNCTION_EXISTS(readv HAVE_READV)
CHECK_FUNCTION_EXISTS(getdtablesize HAVE_GETDTABLESIZE)
CHECK_FUNCTION_EXISTS(sysconf HAVE_SYSCONF)
CHECK_FUNCTION_EXISTS(readv HAVE_READV)