mqcleanup.c

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <semaphore.h>
#include <mqueue.h>

#define MQUEUE_NAME "/eurephiaFW" 
#define EFW_MSG_SIZE 1024

int main() {
        struct mq_attr mqattr;
        mqd_t msgq;
        int prio;

        // Prepare a POSIX Message Queue
        mqattr.mq_maxmsg = 10;
        mqattr.mq_msgsize = EFW_MSG_SIZE;
        mqattr.mq_flags = 0;
        msgq = mq_open(MQUEUE_NAME, O_RDWR | O_CREAT, 0600, &mqattr);
        if( msgq < 0 ) {
                printf("Could not open message queue: %s\n", strerror(errno));
                return 1;
        }

        if( mq_getattr(msgq, &mqattr) == 0 ) {
                long i;
                char buf[1026];

                memset(&buf, 0, 1026);
                if( mqattr.mq_curmsgs > 0 ) {
                        for( i = 0; i < mqattr.mq_curmsgs; i++ ) {
                                if( mq_receive(msgq, &buf[0], 1024, &prio) == -1 ) {
                                        printf("Error while emptying messages from queue: %s\n",
                                                     strerror(errno));
                                } else {
                                        int j;
                                        printf("Removed message on queue:\n");
                                        for( j = 0; j < 1024 ; j++ ) {
                                                printf("%02x [%c] ", buf[j], buf[j]);
                                                if( ((j+1) % 20) == 0 ) {
                                                        printf("\n");
                                                }
                                        }
                                }
                        }
                }
        } else {
                printf("Could not retrieve message queue attributes (%s)\n",
                       strerror(errno));
        }


        if( mq_close(msgq) != 0 ) {
                printf("Could not do close the message queue used for eFW: %s\n",
                       strerror(errno));
        }

#if 0
        if( mq_unlink(MQUEUE_NAME) != 0 ) {
                printf("Could not do close the message queue used for eFW: %s\n",
                             strerror(errno));
        }
#endif
        return 0;
        
}