共享内存的问题请高手指教__shmid_include_message_int_break_

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共享内存的问题请高手指教

来源: 互联网发布时间：2016-01-16

本文导语: extern "C" { #include #include #include #include #include #include #include #include #include } void usage(int argc, char** argv) { printf("%s argumentsn", argv[0]); prin...

extern "C" {
    #include
    #include
    #include
    #include
    #include
    #include
    #include
    #include
    #include
}

void usage(int argc, char** argv)
{
    printf("%s argumentsn", argv[0]);
    printf("-h             help mode.n");
    printf("-c             create shm.n");
    printf("-m    write message into shm.n");
    printf("-r             read message from shm.n");
    printf("-d             destroy shm.n");
}

typedef enum {SHM_UNKNOW = 0, SHM_CREATE, SHM_DESTROY, SHM_WRITE, SHM_READ} SHM_MODE;

#define SHM_KEY 1234
#define SHM_SIZE 1000

/**IPC_ALLOC is solaris specific
*/
#if !defined( IPC_ALLOC )
    #define IPC_ALLOC IPC_CREAT
#endif

/** create shm with SHM_KEY
* @return shmid
*/
int shm_create();

/** open shm with SHM_KEY
* @return shmid
*/
int shm_open();

/** destroy shm which shm key is SHM_KEY
*/
void shm_destroy(int shmid);

/** write a string into shm, the string should be teminated by null.
*/
void shm_write(int, char*);

/** read message from shm
@param the shmid
*/
void shm_read(int shmid);

/** detach from shm
*/
void shm_close(const void* root);

int main(int argc, char** argv)
{
    SHM_MODE shm_mode = SHM_UNKNOW;
    char* message = NULL;
    int shmid = 0;

    int opt = 0 ;
    extern int optind ;
    extern char* optarg ;

    while ((opt = getopt (argc, argv, "hcrm:d")) != EOF) {
        switch (opt) {
            case 'h' :  // help mode
                usage(argc, argv);
                return 0;
            case 'c' :  //create mode
shm_mode = SHM_CREATE;
                break;
case 'd' :  //destroy mode
                shm_mode = SHM_DESTROY;
                break;
            case 'r':   //read message
                shm_mode = SHM_READ;
                break;
            case 'm':   //write message
                shm_mode = SHM_WRITE;
                message = (char*)optarg;
                break;
            default :
                usage(argc, argv);
                return -1;
        }
    }

    switch (shm_mode){
        case SHM_CREATE:
            shmid = shm_create();
            break;
        case SHM_DESTROY:
            shmid = shm_open();
            shm_destroy(shmid);
            break;
        case SHM_READ:
            shmid = shm_open();
            shm_read(shmid);
            break;
        case SHM_WRITE:
            shmid = shm_open();
            shm_write(shmid, message);
            break;
        default:
            usage(argc, argv);
            return -1;
    }
}

int shm_create()
{
    int shmid = shmget (SHM_KEY, SHM_SIZE, IPC_CREAT | 0666);
    if(shmid