网上MessageQ的编程资料

最新推荐文章于 2022-03-12 10:53:56 发布

转载最新推荐文章于 2022-03-12 10:53:56 发布 · 2.7k 阅读

文章标签：

#编程 #class #文档 #buffer

本文介绍MessageQ消息队列的基本操作，包括如何通过编程语言实现消息的发送、接收及队列的连接与断开。提供了具体的C语言代码示例，帮助读者理解MessageQ的工作原理。

网上MessageQ的编程资料

关于MessageQ的编程资料网上比较少，bea提供的文档里有比较详细的说明。多读几次MessageQ的文档就能写出程序来。下面是几个MessageQ的操作函数：

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "p_entry.h"

#include "p_return.h"

#include "p_symbol.h"

#include <unistd.h>

#include <sys/types.h>

/*attach到消息队列里去，qid为消息队列的id*/

int qattach(short qid)

{

q_address q_addr;

int32 attach_mode;

int32 dmq_status;

int32 q_num_len;

int32 q_type;

char q_num_str[4];

int rc;

attach_mode = PSYM_ATTACH_BY_NUMBER;

q_type = PSYM_ATTACH_PQ;

memset(q_num_str, 0x00, 4);

(void)sprintf( q_num_str, "%d", qid );

q_num_len = (int32) strlen( q_num_str );

dmq_status = pams_attach_q( &attach_mode, &q_addr, &q_type,

q_num_str, &q_num_len,

(int32 *) 0,

(char *) 0,

(char *) 0);

if(dmq_status==PAMS__SUCCESS)

{

return(0);

}

else

{

return ( dmq_status );

}

/*从消息队列里detach*/

int32 qdetach( )

{

int32 dmq_status;

dmq_status = pams_exit( );

if(dmq_status==PAMS__SUCCESS)

{

return(0);

}

else

{

return ( dmq_status );

}

/*从消息队列读取消息,msg_area为消息内容，msg_size为读取长度，qid为队列编号*/

int32 qread(char *msg_area, short *msg_size, short *qid)

{

char priority;

q_address msg_source;

short msg_class;

short msg_type;

short msg_area_len;

short msg_data_len;

int32 timeout;

int32 dmq_status;

char *qgroup, *getenv( );

int i;

priority = 0; /* get all messages */

msg_area_len = *msg_size; /* size of the message buffer */

timeout = 0;

dmq_status = pams_get_msgw(

msg_area, /* where msg is written */

&priority, /* get all messages */

&msg_source, /* q_address of sender */

&msg_class, /* class of received msg */

&msg_type, /* type of received msg */

&msg_area_len, /* size of message buffer */

msg_size, /* actual size of the msg */

&timeout,

(int32 *) 0,

(struct PSB *) 0,

(struct show_buffer *) 0,

(int32 *) 0,

(char *) 0 );

if ( dmq_status == PAMS__SUCCESS )

{

return( 0 );

}

else

{

return ( dmq_status );

}

/*往消息队列里发送消息，msg_area为消息内容，msg_size为消息长度，qdest为消息队列编号*/

int32 qwrite(char *msg_area, short msg_size, short qdest)

{

char priority;

char delivery;

char uma;

short msg_class;

short msg_type;

int32 dmq_status;

int32 timeout;

struct PSB put_psb;

char *qgroup, *getenv( );

q_address qdest_addr;

int i;

priority = 0; /* No priority */

msg_class = msg_type = 0; /* No type or class at the moment */

delivery = PDEL_MODE_NN_MEM; /* No Notification and nonrecoverable */

timeout = 100; /* Wait 10 seconds before giving up */

uma = PDEL_UMA_DISCL; /* If can't deliver it, DISCard and Log */

qgroup=getenv("DMQ_GROUP_ID");

qdest_addr.au.queue=(int16)qdest;

qdest_addr.au.group=(int16)atoi(qgroup);

dmq_status = pams_put_msg(

msg_area,

&priority,

&qdest_addr, /* passed in */

&msg_class,

&msg_type,

&delivery,

&msg_size,

&timeout,

&put_psb,

&uma,

(q_address *) 0,

(int32 *) 0,

(char *) 0,

(char *) 0 );

if ( dmq_status == PAMS__SUCCESS )

{

return( 0 );

}

else

{

return ( dmq_status );

}

编译:
[root@localhost src]# cc -o ../bin/test -I $BEADIR/include test.c -L $BEADIR/lib -ldmq
在同一个消息队列中，你也可以根据程序的pid来发送和获得只属于本应用程序的消息。