更新时间:2022-11-14 07:56:13
使用 find
可能会更好:
find . -name "pattern_*" -printf '.' | wc -m
在您的具体情况下:
find . -maxdepth 1 -name "20061101-20131101_kh5x7tte9n_2010_*" -printf '.' | wc -m
find
将返回符合条件的文件列表.-maxdepth 1
将使搜索仅在路径中完成,没有子目录(感谢Petesh!).-printf '.'
将为每个匹配项打印一个点,因此带有新行的名称不会使 wc -m
中断.
find
will return a list of files matching the criteria. -maxdepth 1
will make the search to be done just in the path, no subdirectories (thanks Petesh!). -printf '.'
will print a dot for every match, so that names with new lines won't make wc -m
break.
然后wc -m
会指明与文件数匹配的字符数.
Then wc -m
will indicate the number of characters which will match the number of files.
两种可能方案的性能比较:
Performance comparation of two possible options:
让我们用这个模式创建 10 000 个文件:
Let's create 10 000 files with this pattern:
$ for i in {1..10000}; do touch 20061101-20131101_kh5x7tte9n_201_$i; done
然后用ls -1 ...
或find ...
比较得到结果所需要的时间:
And then compare the time it takes to get the result with ls -1 ...
or find ...
:
$ time find . -maxdepth 1 -name "20061101-20131101_kh5x7tte9n_201_*" | wc -m
10000
real 0m0.034s
user 0m0.017s
sys 0m0.021s
$ time ls -1 | grep 20061101-20131101_kh5x7tte9n_201 | wc -m
10000
real 0m0.254s
user 0m0.245s
sys 0m0.020s
find
快了 5 倍!但是如果我们使用 ls -1f
(再次感谢Petesh!),那么ls
甚至比find
还要快:
find
is x5 times faster! But if we use ls -1f
(thanks Petesh again!), then ls
is even faster than find
:
$ time ls -1f | grep 20061101-20131101_kh5x7tte9n_201 | wc -m
10000
real 0m0.023s
user 0m0.020s
sys 0m0.012s