c - 为什么我的简单 pthreads 程序会因段错误而崩溃？

Question

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdio.h>
#include <stdlib.h>
#include<signal.h>
#include<unistd.h>//getch();
#include <termios.h>//getch();
#include <pthread.h>
volatile sig_atomic_t flag = 0;

char getch()
{
  int buf=0;
  struct termios old= {0};
  fflush(stdout);
  if(tcgetattr(0, &old)<0)
    perror("tcsetattr()");
  old.c_lflag&=~ICANON;
  old.c_lflag&=~ECHO;
  old.c_cc[VMIN]=1;
  old.c_cc[VTIME]=0;
  if(tcsetattr(0, TCSANOW, &old)<0)
    perror("tcsetattr ICANON");
  if(read(0,&buf,1)<0)
    perror("read()");
  old.c_lflag|=ICANON;
  old.c_lflag|=ECHO;
  if(tcsetattr(0, TCSADRAIN, &old)<0)
    perror ("tcsetattr ~ICANON");
  //printf("%c\n",buf);//to print the value typed.
  return buf;
}

void *send_function()
{
  printf("\n Send Thread \n");
  //return 0;
}

void my_function(int sig)
{ // can be called asynchronously
  flag = 1; // set flag
}

int main ()
{
  char selection;//user input(s or r)
  pthread_t send;
  while(1)
  {  
    signal(SIGINT, my_function);
    //printf("\n Before SIGINT \n");            
    if(flag)
    { 
        printf("\n Choose your terminal S or R \n");
        selection=getch();
        flag = 0;
    }   
    if(selection=='s')
        if(pthread_create(&send,NULL,send_function(),NULL))
        {
        fprintf(stderr, "Error creating thread\n");
        return 1;
        }
    else if(selection=='r')
        printf("Receive Function is received");
    //printf("\n After SIGINT \n"); 
 }
  return 0;  

} 

输出:

 nivas@balakrishnan-HCL-Desktop:~/C_sample$ gcc -pthread -o thread thread.c

 nivas@balakrishnan-HCL-Desktop:~/C_sample$ ./thread

 Choose your terminal S or R

 Send Thread

 Send Thread

 Send Thread

 Send Thread

 Send Thread
 Segmentation fault (core dumped)
 nivas@balakrishnan-HCL-Desktop:~/C_sample$ ^C
 nivas@balakrishnan-HCL-Desktop:~/C_sample$

在上面的程序中，我遇到了段错误。我需要的输出是在我按下 's' 后连续打印 "Send Thread"。我已经研究过以前的类似问题，但找不到答案。谁能帮帮我？

Answer 1

是这一行:

if(pthread_create(&send,NULL,send_function(),NULL))

打字错误？ pthread_create 的第三个参数是一个函数指针，线程应该从这里开始。

它应该是:

if(pthread_create(&send,NULL,send_function,NULL))

此外，您创建的线程不会真正退出，除非您将它们的属性位设置为分离，或显式分离它们，或使用 pthread_join 收集状态。