花费时间: 测量linux下运行某个命令花费的时间
time cmd;
例如:
~ # time find ./ -name 'start'
./mnt/SATA/start
./sys/block/sda/sda1/start
./sys/block/ndda/ndda1/start
real 0m 0.94s
user 0m 0.36s
sys 0m 0.58s
~ # time
BusyBox v1.4.2 (2009-08-19 14:30:22 KST) multi-call binary
Usage: time [OPTION]... COMMAND [ARGS...]