Send data to parent process in Qt

[PstdEr]

I have an application where i launched a process (using QProcess) , from this process i need to send a message to parent process.

from parent

int msgid = msgget(0x1234,IPC_CREAT|0666);
    char str[50];
    qDebug() << "waiting for msg ";
        msgrcv(msgid,str,sizeof str,0,0);
 
    if (!strcmp(str,"sender")){
        /*do some processing */
    }

int msgid = msgget(0x1234,IPC_CREAT|0666);
    char str[50];
    qDebug() << "waiting for msg ";
        msgrcv(msgid,str,sizeof str,0,0);

    if (!strcmp(str,"sender")){
        /*do some processing */
    }

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from the child

int msgid = msgget(0x1234,IPC_CREAT|0666);
    char str[]="sender";
    qDebug() << "sending  for msg ";
    msgsnd(msgid,str,strlen(str)+1,0);

int msgid = msgget(0x1234,IPC_CREAT|0666);
    char str[]="sender";
    qDebug() << "sending  for msg ";
    msgsnd(msgid,str,strlen(str)+1,0);

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i am getting a msg "waiting for msg" and system is going to hang. what is the problem?

how else will pass msg from one process to other.

Thanks.