我想知道是否有人可以帮我修改我当前的代码....
目前,它使用fork()创建我的进程,并获取指向执行该子代码块的函数的指针 .
我想玩管道并尝试让Process Y将其pid发送到Process X然后我想将它发送回Main ...
这是我目前所拥有的
#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <stdlib.h> // exit
#include <fcntl.h>
#include <sys/wait.h>
void processX();
void processY();
pid_t addChild(void (*childPtr) (), int fileDes[2]) {
pid_t cpid;
if((cpid=fork()) == 0) {
pipe(fileDes);
childPtr(fileDes);
wait(NULL);
exit(0);
} else if (cpid < 0) {
printf("failed to fork");
exit(1);
} else {
}
return cpid;
}
void processY(int fileDes[2]) {
printf("Child Y[%d] Created of Parent X[%d]\n", getpid(), getppid());
printf("We are now going to write Y PID to process X\n");
pid_t a = getpid();
char buf[1024]; // child reads from pipe() to buffer
close(fileDes[0]); // close reading end of the pipe
write(fileDes[1], &a, sizeof(buf) / sizeof(int));
}
void processX(int fileDes[2]) {
printf("Child X[%d] Created of parent Main[%d]\n", getpid(), getppid());
int status;
pid_t Y = addChild(processY, fileDes);
wait(&status);
pid_t new_val = 5;
close(fileDes[1]); // closing the writing end of the pipe.
read(fileDes[0], &new_val, sizeof(new_val));
printf("Message read with number %d: \n", new_val);
}
int main() {
int status;
int fd[2];
printf("Main process[%d]\n", getpid());
pid_t root = addChild(processX, fd);
wait(&status);
printf("We are going to read from X to Main and then return the Value we got from Y\n");
return 0;
}
我不知道从Y - X然后X - Main创建一个管道....
Y ---->发送pid ----> X收到Y pid -----向主要发送新信息--->主要打印接收数据......
1 回答
我想出了我的答案