LINUX 写log【原】

void log_file( const int pid,const char * str_fmt,...)
{
    FILE *fp;

    fp = fopen("myfile.txt", "a");
   
    if(fp)
    {
        static char log_trace[256];
        va_list ap;
        struct tm *tm;
        time_t t;
    
        va_start(ap, str_fmt);
        vsnprintf(log_trace, sizeof(log_trace), str_fmt, ap);
        va_end(ap);

        t = time(NULL);
        tm = localtime(&t);
        fprintf(fp, "[%02d/%02d/%02d/ %02d:%02d:%02d]: %s pid:%d\n", 
                    tm->tm_year, 
                    tm->tm_mon, 
                    tm->tm_mday, 
                    tm->tm_hour, 
                    tm->tm_min, 
                    tm->tm_sec,
                    log_trace,pid);
        fclose(fp);
    }


}

比较常用的一种，还有其它的方式~后面再补充