[ 20.395701] systemd-udevd[251]: starting version 204
cheng@chpc:~/download/systemd-218$ grep -r "starting version" ./*
./src/udev/udevd.c: log_info("starting version " VERSION);
/usr/src/linux-3.18.4/include/linux/syslog.h中有do_syslog()函数的声明
int do_syslog(int type, char __user *buf, int count, bool from_file);
/usr/src/linux-3.18.4/kernel/printk/printk.c文件中有do_syslog()函数的定义
原文：http://blog.csdn.net/oldlinux/article/details/43491749