| BobS0327 |
11-06-2006 07:03 PM |
shmget returns invalid segment size specified
My OS is Fedora Core 5 and I get a EINVAL error, Invalid segement size specified on the shmget function below. The value of shared_data_size variable is 9,216,964. I used sysctl to determine the value of kernel.shmmax. This value is 33,554,433.
Anybody have any suggestions?
Code:
int getsharedmem(vodi)
{
long long shm_key=0x7a6d2000;
size_t shared_data_size = sizeof(SharedData) +
sizeof(TriggerData) +
((*monitor[cam]->image_buffer_count)*(sizeof(struct timeval))) +
((*monitor[cam]->image_buffer_count)*(*monitor[cam]->width)*(*monitor[cam]->height)*3);
int shmid;
if((shmid=shmget((shm_key&0xffffff00)|monitor[cam]->mon_id,shared_data_size,SHM_R))==-1)
{
printf("Failed to shmget error = %s\n",strerror(errno));
if(errno == EINVAL)
printf("Invalid segment size specified\n");
else if(errno == EEXIST)
printf("Segment exists, cannot create it\n");
else if(errno == EIDRM)
printf("Segment is marked for deletion or was removed\n");
else if(errno == ENOENT)
printf("Segment does not exist\n");
else if(errno == EACCES)
printf("Permission denied\n");
else if(errno == ENOMEM)
printf("Not enough memory to create segment\n");
printf("monitor[%d]->mon_id = %d shared_data_size = %d\n",cam, monitor[cam]->mon_id,shared_data_size);
// The above errno returns "Invalid argument"
fprintf(stderr,"ERROR: Failed to shmget\n");
return EXIT_FAILURE;
}
return 0;
}
|
