export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/userdata:/userdata/lib export PATH=$PATH:/userdata/valgrind/bin
tcpdump -i eth0 tcp port 5683 -w log.cap
echo 4 4 1 7 > /proc/sys/kernel/printk
mount -o nolock,tcp -t nfs 192.168.1.177:/home/ppq/nfs /mnt
线程同步:互斥锁 自旋锁 读写锁,条件变量,信号量
进程间通信:管道(Pipe)和有名管道(FIFO)、信号(Signal)、消息队列(Message Queue)、共享内存(Shared Memory)、信号量(Semaphore)、套接字(Socket)
vi /etc/resolv.conf
nameserver 114.114.114.114
nameserver 223.5.5.5