Linux-如何查找最近12个小时内未查找命令更改的文件

Question

I need to find files modified in the last 12 hours. However, the directory is quite large so using the usual find command takes way too long.

Anyone have any ideas doing this quicker? I was thinking something like listing the files, then using head to get the top 20 and then check those files only. But I'm not sure.

Any help?

UPDATE: Thanks to the help of the chosen answer, we have figured out that you can actually find a file without using the find command. The trick is to timestamp the file names, then use the following code to get the latest one:

ls -1 /directory/files*.txt | sort -nr | head -1

Answer 1

The file modification time is stored in its inode. So whatever command you use has to read inodes for all files in that directory. You can make your own script for checking the mtime, but it won't be faster.

Listing the directory contents (filenames only) is really fast, try with ls -1 ( ls minus one ).But listing it with file attributes like mtime is slow: ls -l ( ls minus little L ).

The file list in directory is read in "random" order by the filesystem (the order depends on many things, but is static). So you can't use something like stopping after X number of files. ls -t lists the files sorted by mtime, but it has to read the mtime of all files in order to sort them.