examples/PIPS/IPC/src/parent/ipcparent.c

// ipcparent.c
//
// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

//

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <errno.h>
#include <spawn.h>
#include <string.h>
#include <sys/wait.h>

char PressKey()
        {
        char ch;
        fflush(stdout);
        ch=getchar();
        return ch;
        }

int Error(char msg[])
        {
        printf("%s [Error NUMBER = %d]\n",msg,errno);
        PressKey();
        return EXIT_FAILURE;
        }

int main()
        {
        FILE* childProcessStream;
        char fifoFileName[] = "myfifofile";
        char fifoExecFileName[] = "z:\\sys\\bin\\fifochild";
        char popenExecFileName[] = "z:\\sys\\bin\\ipcchild";
        pid_t fifoChildPid;
        int fifoRetVal;
        int unlinkResult;
        int fifoResult;
        int     childProcessFD;
        
        char **argv=(char**)malloc(2*sizeof(char*));
    argv[0]=(char*)malloc(50*sizeof(char));
        argv[1] = 0;
        strcpy(argv[0], fifoExecFileName);

    unlinkResult=unlink(fifoFileName);
        fifoResult = mkfifo(fifoFileName,S_IXGRP);
        if(fifoResult == -1)
                {
                        Error("*** failure mkfifo ***");
                        PressKey();
                        return EXIT_FAILURE;
                }
        fifoRetVal  = posix_spawn(&fifoChildPid, fifoExecFileName, NULL, NULL, argv, (char**)NULL);
        free((void*)argv[0]);
        free((void*)argv);
        if(fifoRetVal != 0)
                {
                printf("failure posix_spawn [Error NUMBER = %d]\n",errno);
        unlinkResult=unlink(fifoFileName);
        if(unlinkResult!=0)
            {
            printf("failure posix_spawn [Error NUMBER = %d]\n",errno);
            }
                PressKey();
                return EXIT_FAILURE;
                }
        else
                {
                int fifoFd = open(fifoFileName,O_RDONLY);
                if(fifoFd == -1)
                        {
                        Error("*** failure FIFO Open ***");
                        PressKey();
                        return EXIT_FAILURE;
                        }
                else
                        {
                        char buffer[100];
                        int nbytes;
                        memset(buffer,0,sizeof(buffer));
                        nbytes = read(fifoFd,buffer,sizeof(buffer));
                        printf("\nBytes Received=%d, Message Received from fifochild using [FIFO]=%s",nbytes,buffer);
                        (void)close(fifoFd);
                        }
                childProcessStream = popen(popenExecFileName,"r");
                if(childProcessStream == NULL)
                        {
                        Error("\n Failure to create child process with popen()");
                        PressKey();
                        return EXIT_FAILURE;
                        }
                else
                        {
                        char buffer[100];
                        int nbytes;
                        childProcessFD = fileno(childProcessStream);
                        memset(buffer,0,sizeof(buffer));
                        printf("\n\nWaiting for message from Child[popen()]\n");
                        nbytes = read(childProcessFD,buffer,sizeof(buffer));
                        printf("Bytes Received=%d, Message Received from ipcchild using[popen()]=%s\n[ok]\n",nbytes,buffer);
                        pclose(childProcessStream);
                        }
                (void)waitpid(fifoChildPid,NULL,0);
                unlinkResult=unlink(fifoFileName);
                if(unlinkResult!=0)
                        {
                        Error("Unlink error");
                        }
                }
        printf("Press any key to exit...");
        PressKey();
        return EXIT_SUCCESS;
        }

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