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我在課堂上有很多麻煩，任何幫助都很棒。我需要這段代碼來創建4個生成器線程，這些線程可以持續循環並將SIGUSR1或SIGUSR2發送到4個消費者線程。 2只響應SIGUSR1，2只響應SIGUSR2。這些信號由製作者發送，並由消費者接收，但之後沒有任何反應，程序崩潰。下面是該程序，並在運行時從GDB輸出。C pthreads和信號發送
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <semaphore.h>
#include <signal.h>
#include <time.h>
#define NP 4
#define NC1 2
#define NC2 2
#define CNT 10
void handler1(int);
void handler2(int);
typedef struct {
int sent;
int received;
int buf[1];
int SIG1;
int SIG2;
sem_t con;
sem_t prod;
} sbuf_t;
sbuf_t buff;
pthread_t threads[9];
void *producer() {
srand(time(0));
int s,i;
while(1){
sem_wait(&buff.prod);
s=(rand()%2)+1;
//printf("prod ready \n");
if(s==1){
buff.sent++;
for(i=0;i<4;i++){
pthread_kill(threads[i],SIGUSR1);}
}
else if(s==2){
buff.sent++;
for(i=0;i<4;i++){
pthread_kill(threads[i],SIGUSR1);}
}
usleep(rand()%100000);
sem_post(&buff.prod);
}
}
void *consumer1() {
signal(SIGUSR1, handler1);
//printf("waiting 1\n");
while(1){
}
}
void *consumer2() {
signal(SIGUSR2, handler2);
//printf("waiting 2\n");
while(1){
}
}
void handler1(int signum){
printf("Caught 1\n");
if(signum==SIGUSR1){
sem_wait(&buff.con);
buff.received++;
buff.SIG1++;
sem_post(&buff.con);
}
}
void handler2(int signum){
printf("caught 2 \n");
if(signum==SIGUSR2){
sem_wait(&buff.con);
buff.received++;
buff.SIG2++;
sem_post(&buff.con);
}
}
void main(){
buff.SIG1=0;
buff.SIG2=0;
buff.sent=0;
buff.received=0;
int index;
sem_init(&buff.con, 0, 1);
sem_init(&buff.prod, 0, 1);
for (index = 0;index < NC1;index++) {
pthread_create(&threads[index], NULL, consumer1,NULL);
}
for (index = 0;index < NC2;index++) {
pthread_create(&threads[index+2], NULL, consumer2,NULL);
}
for (index = 0; index < NP; index++) {
pthread_create(&threads[index+4], NULL, producer,NULL);
}
和gdb
(gdb) run
Starting program: /home/eric/a.out
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff77f6700 (LWP 4944)]
[New Thread 0x7ffff6ff5700 (LWP 4945)]
[New Thread 0x7ffff67f4700 (LWP 4946)]
[New Thread 0x7ffff5ff3700 (LWP 4947)]
[New Thread 0x7ffff57f2700 (LWP 4948)]
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff5ff3700 (LWP 4947)]
consumer2() at lab3.c:68
68 }
(gdb) continue
Continuing.
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff67f4700 (LWP 4946)]
consumer2() at lab3.c:68
68 }
(gdb)
Continuing.
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff6ff5700 (LWP 4945)]
consumer1() at lab3.c:60
60 }
(gdb)
Continuing.
[New Thread 0x7ffff4ff1700 (LWP 4949)]
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff77f6700 (LWP 4944)]
consumer1() at lab3.c:60
60 }
(gdb)
Continuing.
Caught 1
Caught 1
Caught 1
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff5ff3700 (LWP 4947)]
consumer2() at lab3.c:68
68 }
(gdb)
Continuing.
Caught 1
[New Thread 0x7ffff47f0700 (LWP 4950)]
Caught 1
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff67f4700 (LWP 4946)]
consumer2() at lab3.c:68
68 }
(gdb)
Continuing.
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff6ff5700 (LWP 4945)]
consumer1() at lab3.c:60
60 }
(gdb)
Continuing.
Caught 1
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff77f6700 (LWP 4944)]
consumer1() at lab3.c:60
60 }
(gdb)
Continuing.
Caught 1
[New Thread 0x7ffff3fef700 (LWP 4951)]
Caught 1
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff5ff3700 (LWP 4947)]
consumer2() at lab3.c:68
68 }
(gdb)
Continuing.
Program received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff67f4700 (LWP 4946)]
consumer2() at lab3.c:68
68 }
(gdb)
Continuing.
Caught 1
[Thread 0x7ffff3fef700 (LWP 4951) exited]
[Thread 0x7ffff47f0700 (LWP 4950) exited]
[Thread 0x7ffff4ff1700 (LWP 4949) exited]
[Thread 0x7ffff57f2700 (LWP 4948) exited]
[Thread 0x7ffff5ff3700 (LWP 4947) exited]
[Thread 0x7ffff67f4700 (LWP 4946) exited]
[Thread 0x7ffff7fda740 (LWP 4940) exited]
Cannot find user-level thread for LWP 4945: generic error
(gdb)
Continuing.
Cannot execute this command without a live selected thread.
(gdb)