最好别用

瑾哥.我肝的

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <semaphore.h>
#include <fcntl.h>
#include <wait.h>
int main(){
sem_t *sem = NULL;
pid_t pid;
pid = fork();
setbuf(stdout,NULL);
char msg[] = "This is the race condition test\n";
char* ptr;
int c;
if (pid == 0){
sem = sem_open("sem1", O_CREAT|O_RDWR, 0666, 1);
for(int i=0; i < 10;i++)
{
sem_wait(sem);
for(ptr = msg; (c = *ptr)!= 0; ptr++)
putc(c,stdout);
sem_post(sem);
}
sem_close(sem);
}
else {
sem = sem_open("sem1", O_CREAT|O_RDWR, 0666, 1);
for(int i=0; i < 10;i++)
{
sem_wait(sem);
for(ptr = msg; (c = *ptr)!= 0; ptr++)
putc(c,stdout);
sem_post(sem);
}
sem_close(sem);
wait(NULL);
}
sem_unlink("sem1");
return 0;
}

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <wait.h>
int main(){
pid_t pid;
pid = fork(); // Create the new process
setbuf(stdout,NULL); // Set unbuffered
char msg[] = "This is the race condition test\n"; // used to show the race condition
char* ptr;
int c;
// child process
if (pid == 0){
for(int i=0; i < 10;i++)
{
for(ptr = msg; (c = *ptr)!= 0; ptr++)
putc(c,stdout);
}
}
// parent process
else {
for(int i=0; i < 10;i++)
{
for(ptr = msg; (c = *ptr)!= 0; ptr++)
putc(c,stdout);
}
wait(NULL);
}
return 0;
}