syslog 守护进程的实现

#include
#include
#include
#include
#include
#include
#include

#define MAXFILE 65535

int main()
{
        pid_t pc,sid;
        int i,fd,len;
        char *buf="This is a Dameon \n";
        len=strlen(buf);
        pc=fork();
        if(pc<0)
        {
                perror("fork errror!");
                exit(1);
        }
        else if(pc>0)
                exit(0);
        openlog("dema_update",LOG_PID,LOG_DAEMON);
        syslog(LOG_ERR, "%s\n", "setsid");
 
       if((sid=setsid())<0)
        {
                syslog(LOG_ERR,"%s\n","setsid");
                exit(1);
        }

        if((sid=chdir("/"))<0)
        {
                syslog(LOG_ERR,"%s\n","chdir");
                exit(1);
        }

        umask(0);
        for(i=0;i        close(i);

        while(1)
        {
                if((fd=open("/tmp/dameon.log",O_CREAT|O_WRONLY|O_APPEND,0600))<0)
                {
                        syslog(LOG_ERR,"open");
                        exit(1);
               
                }
                write(fd, buf, len+1);
                close(fd);
                sleep(10);
        }
        closelog();
        exit(0);
}