将__O_CLOEXEC变为O_CLOEXEC，便于移植

swapi/subjects/serial/serial.c

@@ -59,7 +59,7 @@ void *serial_open(const char *serialName, int baudrate, const char *parityCheck
     }
 
     /* 2, 打开串口 */
-    pSerial->fd = open(pSerial->name, O_RDWR | O_NOCTTY | O_NDELAY | __O_CLOEXEC);
+    pSerial->fd = open(pSerial->name, O_RDWR | O_NOCTTY | O_NDELAY | O_CLOEXEC);
     if(pSerial->fd == -1) goto ErrorP;
 
     if(flock(pSerial->fd, LOCK_EX | LOCK_NB) == -1) goto ErrorP;