将查找输出作为参数传递时出现“参数列表太长”错误

Question

I have some 5 million text files under a directory - all of the same format (nothing special, just plain text files with some integers in each line). I would like to compute the maximum and minimum line count amongst all these files, along with its two filenames (the one for max and another for min).

I started out by trying to write out all the line count like so (and then workout how to find the min and max from this list):

wc -l `find /some/data/dir/with/text/files/ -type f` > report.txt

but this throws me an error:

bash: /usr/bin/wc: Argument list too long

Perhaps there is a better way to go about this?

Answer 1

There is a limit to the argument list length. Since you have several millions files passed to wc, the command certainly crossed this line.

Better invoke find -exec COMMAND instead:

find /some/data/dir/with/text/files/ -type f -exec wc -l {} + > report.txt

Here, each found file find will be appended to the argument list of the command following -exec in place of {} . Before the argument length is reached, the command is run and the remaining found files will be processed in a new run of the command the same way, until the whole list is done.

See man page of find for more details.

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Thanks to Charles Duffy for the improvements of this answer.