uncached

只打印新行，或者那些有一段时间没有见过的行

用法

不带参数时，uncached 会删除重复的行

$ cat /tmp/inputs.txt
one
two
one
three
uncached$ cat /tmp/inputs.txt | uncached
one
two
three

可以提供缓存文件以避免在一定时间内出现重复行

$ cat /tmp/inputs.txt
one
two
three
$ # new values are printed
$ cat /tmp/inputs.txt | uncached -c /tmp/in.cache
one
two
three
$ # values are not printed
$ cat /tmp/inputs.txt | uncached -c /tmp/in.cache
$ sleep 5
$ # values older than 4 seconds are printed
$ cat /tmp/inputs.txt | uncached -c /tmp/in.cache
one
two
three
$ echo four >> /tmp/inputs.txt
$ # new values are printed
$ cat /tmp/inputs.txt | uncached -c /tmp/in.cache
four