错误：sem_union的存储⼤⼩未知问题的解决⽅法 今天在编译代码的时候提⽰错误: ‘sem_union'的存储⼤⼩未知 问题原因:在新版2.6内核中关于union sem_union 这个联合体已经被注释了,需要⾃⼰写这个联合体.解决⽅案:在C⽂件中先定义:union semun { int val;struct semid_ds *buf;unsigned ...
union semun int val; struct semid_ds *buf; unsigned short *array; sem_union; 随后编译时它就能找到预先定义好的sem_union联合体了。
union semun { int val; // 用于设置信号量的值 struct semid_ds *buf; // 用于获取或设置信号量集的信息 unsigned short *array; // 用于读取或修改整个信号量集 }; 这样,当你在代码中使用`sem_union`时,编译器就能识别其结构,从而避免错误。 在编程中,遇到类似的问题,通常需要检查你的代码是否与当前环...
这个也叫共用体，用法跟结构体有点相同，但数据存储“空间”跟结构体不一样，具体用法参照http://baike.baidu.com/link?url=Ayg3do4Cy4aEK0JMO74-TRZcEHZ62x-A2gmsjKi-ZlCMiZcaDbOi26sAr8ui23mD7tBzk1LfS81A3bnMOJk9-a
struct sembuf struct sembuf _sf和union semun,结构体的定义如下:1.structsembuf2.{3.shortintsem_num;/*信号量的序号从0~nsems-1*/4.shortintsem_op;/*对信号量的操作,>0,0,<0*/5.shortintsem_flg;/*操作标识:
需手工加一个结构定义就可以了 union semun { int val;struct semid_ds *buf;unsigned short int *array;struct seminfo *__buf;};
union semun fourth; unsigned long fourth; int err, err2; struct semid64_ds s64; struct semid64_ds __user *up64; @@ -249,9 +249,13 @@ static long do_compat_semctl(int first, int second, int third, u32 pad) memset(&s64, 0, sizeof(s64)); if ((third & (~IPC_64)) =...
union semun { int val; /* value for SETVAL */ struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */ u_short *array; /* array for GETALL & SETALL */ }; At the end of the day, I'm just trying to get a working bonnie++. ...
Hi, What's the story behind "__attribute__ ((transparent_union))" for union semun in <linux/sem.h>? When building for non-OpenRISC using an OpenRISC tree, I get the following compiler warning: include/uapi/linux/sem.h:45:7: warning: union cannot be made transparent Thx! Gr{oetje...
structsembufstructsembuf _sf和unionsemun 结构体的定义如下: 1.structsembuf 2. { 3. short int sem_num; /* 信号量的序号从0~nsems-1 */ 4. short int sem_op; /* 对信号量的操作,>0, 0, <0 */ 5. short int sem_flg; /* 操作标识: ...