$ ipcs -q
  ------ メッセージキュー --------
  キー      msqid     所有者    権限      使用バイト数メッセージ  
  
  0x6e03b930 0         hoge     666       0           0           
  0x7a03b92f 385       hoge     666       1152        48         
  
  $ ipcrm msg 385
  リソースを削除しました
		 

		
  #ifndef __SHM_COMMON_H__
  #define __SHM_COMMON_H__
  #define KEYFILE_PATH   "shm-write"
  #define PROJ_CHAR      (char)'x'
  #define SHMSIZE   (360)
  #endif
		

		
  /* ------------------------------------------------------------
     This program is one of the implementations for shared memory ;
     writing side to shared memory
  
     Written by Kazutomo Yoshii  
     ------------------------------------------------------------ */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <errno.h>
  #include <math.h>
  #include <sys/ipc.h>
  #include <sys/shm.h>
  
  #include "shm-common.h"
  static char char_sin( int d, int p )
  {
    return (char)( sin(((double)d/180.0 * M_PI) +
                       ((double)p/180.0 * M_PI) ) * 127 ) ;
  }
  int main(int argc, char *argv[]) 
  {
    key_t  key; 
    int    shmid;
    char   *shmaddr;
    int    i;
  
    /* generation of key */
    key = ftok(KEYFILE_PATH,PROJ_CHAR);
    if( key == -1 ) {
      perror("ftok()");
      return 1;
    }
    
    shmid = shmget(key, SHMSIZE, IPC_CREAT| IPC_EXCL| 0600 );
    if( shmid == -1 ) {
      perror("shmget()");
      return 1;
    }
    shmaddr = shmat(shmid, NULL, 0);
    if( shmaddr == (char*)-1 ) {
      perror("shmat()");
      return 1;
    }
    for( i=0; i<360; i++ ) {
      shmaddr[i] = char_sin( i, 0 );
    }
    sleep(2);
    if( shmctl( shmid, IPC_RMID, NULL) == - 1 ) {
      perror("shmctl()");
      return 1;
    }
    return 0;
  }
		

		
  /* ------------------------------------------------------------
     This program is one of the implementations for shared memory ;
     reading side to shared memory
     Written by Kazutomo Yoshii  
     ------------------------------------------------------------ */
  #include <stdio.h>
  #include <stdlib.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <errno.h>
  #include <math.h>
  #include <sys/ipc.h>
  #include <sys/shm.h>
  #include "shm-common.h"
  int main(int argc, char *argv[]) 
  {
    key_t  key; 
    int    shmid;
    char   *shmaddr;
    int    i;
    /* generation of key */
    key = ftok(KEYFILE_PATH,PROJ_CHAR);
    if( key == -1 ) {
    perror("ftok()");
    return 1;
    }
  
    shmid = shmget(key, SHMSIZE, 0 );
    if( shmid == -1 ) {
      perror("shmget()");
      return 1;
    }
    shmaddr = shmat(shmid, NULL, SHM_RDONLY);
    if( shmaddr == (char*)-1 ) {
      perror("shmat()");
      return 1;
    }
    for( i=0; i<360; i++ ) {
      printf("%d\n", (int)(shmaddr[i]) );
    }
    return 0;
  }
		

		
[プログラムリスト 2-1: mq-common.h : ヘッダーファイル]
#ifndef __MQ_COMMON_H__
#define __MQ_COMMON_H__
#define KEYFILE_PATH   "mq-server"
#define PROJ_CHAR      (char)'z'
#define BUFLEN         (128)
typedef struct {
  long     type;   /* type of message */
  size_t   len;    /* 0 <= length of buf < BUFLEN
                      : -1 means no more data */  
  char     buf[BUFLEN];
} MsgBuf;
#endif
		

/* ------------------------------------------------------------
  This program is one of the server implementations for message
  queues.
  Written by Kazutomo Yoshii  
  ------------------------------------------------------------ */
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <math.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include "mq-common.h"

static char char_sin( int d, int p )
{
  return (char)( sin(((double)d/180.0 * M_PI) +
		     ((double)p/180.0 * M_PI) ) * 127 ) ;
}


static int send_messages_wait(int msgid)
{
  MsgBuf data[2]; 
  int    pos = 0;
  int    t;

  data[0].len = data[1].len = -1;
  data[0].type =  1;
  data[1].type =  2;

  t = 0;
  pos=0;
  while( t<360 ) {
    data[0].buf[pos] = char_sin( t,  0 );
    data[1].buf[pos] = char_sin( t, 90 );
    pos ++;

    if( pos == BUFLEN ) {
      data[0].len = data[1].len = pos;
      if( msgsnd(msgid,(struct msgbuf*)&(data[0]),sizeof(MsgBuf),0)==-1 ) {
	perror("msgsnd()");
	return 1;
      }
      if( msgsnd(msgid,(struct msgbuf*)&(data[1]),sizeof(MsgBuf),0)==-1 ) {
	perror("msgsnd()");
	return 1;
      }
      pos = 0;
    }
    t++;
  }

  if( pos > 0 ) {
    data[0].len = data[1].len = pos;
    if( msgsnd(msgid,(struct msgbuf*)&(data[0]),sizeof(MsgBuf),0)==-1 ) {
      perror("msgsnd()");	
      return 1;
    }
    if( msgsnd(msgid,(struct msgbuf*)&(data[1]),sizeof(MsgBuf),0)==-1 ) {
      perror("msgsnd()");
      return 1;
    }
  } 

  /* to inform 'no more data' to client */ 
  data[0].len = data[1].len = -1;
  if( msgsnd(msgid,(struct msgbuf*)&(data[0]),sizeof(MsgBuf),0)==-1 ) {
    perror("msgsnd()");	
    return 1;
  }
  if( msgsnd(msgid,(struct msgbuf*)&(data[1]),sizeof(MsgBuf),0)==-1 ) {
    perror("msgsnd()");
    return 1;
  }


  /* wait for client */
  printf("waiting for client terminated\n");
  data[0].len = data[1].len = -1;

  for(;;) {
    struct msgbuf rcvbuf;

    if( msgrcv(msgid, &rcvbuf, sizeof(struct msgbuf),
	       1, IPC_NOWAIT) != -1 ) {
      printf("client terminated : type %d\n",1);
      data[0].len = 0;
    }
    if( msgrcv(msgid, &rcvbuf, sizeof(struct msgbuf),
	       2, IPC_NOWAIT) != -1 ) {
      printf("client terminated : type %d\n",2);
      data[1].len = 0;
    }

    if( data[0].len==0 && data[1].len==0 ) break;
  }
  return 0;
}


int main(int argc, char *argv[])
{
  key_t  key;
  int    msgid;
  int    rc;
  

  /* generation of key */
  key = ftok(KEYFILE_PATH,PROJ_CHAR);
  if( key == -1 ) {
    perror("ftok()");
    return 1;
  }
  
  msgid = msgget(key, IPC_CREAT | IPC_EXCL | 0666 ) ;
  if( msgid == -1 ) {
    msgid = msgget(key, IPC_EXCL | 0666 ) ;
    if( msgid == -1 ) {
      perror("msgget()");
      return 1;
    }
  }

  rc = send_messages_wait(msgid);
  if( rc ) return 1;

  /* close */
  msgctl(msgid, IPC_RMID, NULL);

  return 0;
}
		

  /* ------------------------------------------------------------
    This program is one of the client implementations for message
    queues.
    Written by Kazutomo Yoshii  
    ------------------------------------------------------------ */
 
  #include <stdio.h>
  #include <stdlib.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <errno.h>
  #include <sys/stat.h>
  #include <sys/types.h>
  #include <sys/ipc.h>
  #include <sys/msg.h>
  #include "mq-common.h"

static MsgBuf data;

static int rcv_messages_print(int msgid, int type)
{
  int i;
  int rc;
  struct msgbuf  sndbuf;

  for(;;) {
    if( (rc=msgrcv(msgid,(struct msgbuf *)&data,
		   sizeof(MsgBuf),type,0) ) == -1 ) {
      perror("msgrcv()");
      return 1;
    }

    if(data.len == -1 ) break;

    for( i=0; i< data.len; i++ ) {
      printf("%d\n", (int) (data.buf[i]));
    }
  }

  /* to inform disconnection to server */
  sndbuf.mtype = type;
  rc = msgsnd(msgid, &sndbuf ,sizeof(struct msgbuf), 0 ); 

  return 0;
}



int main(int argc, char *argv[])
{
  key_t  key;
  int    msgid;
  int    rc;
  int    type;

  if( argc<2 ) {
    printf("Usage : %s  message_type\n", argv[0]);
    return 1;
  } 

  type = atoi( argv[1] );

  /* generation of key */
  key = ftok(KEYFILE_PATH,PROJ_CHAR);
  if( key == -1 ) {
    perror("ftok()");
    return 1;
  }

  /* connect to the message queu */
  msgid = msgget(key, IPC_EXCL);
  if( msgid == -1 ) {
    perror("msgget()");
    return 1;
  }

  rc = rcv_messages_print(msgid,type);

  if( rc ) return 1;
  return 0;
}