


In Linux, conditional query can be implemented through the "find" command. Its syntax is such as "find / -name file", which is used to specify the directory search. The parameter "-name" represents the target name.
The conditional search command in Linux is the find command.
Linux-The operation method of using the file search command find is as follows:
1. Search the entire disk or specify a directory search. find Search directory -name target name, find / -name file
2. In this way, the search will see an exact match of file, which is case-sensitive. You can use -iname, which is not case-sensitive, find / - iname file. In this way we can find more relevant files in uppercase letters.
3. We first use the * wildcard character to match the relevant files containing file. It is case-sensitive: find / -name *file*. Case-insensitive: find / -iname *file*. If you match like this, there will be more files, and the more precise the match, the easier it will be for searching.
4. find search directory -size file size. Next we search for files larger than 100MB, which should actually be 102400KB*2. All search commands are: find / -size 204800. The - sign means less than, writing the number directly means equal to.
5. find search directory -user username. Here is the search for files belonging to the username user1. How to add and delete usernames in Linux, you can refer to the Linux user management command: find / -user user1.
6. Find search directory -type d. Find all directories under a directory: find /tmp -type d.
7. Find search directory -cmin -time (unit: minutes). Search for files modified within 1 hour under etc. There are too many files under the root directory. Specify a directory: find /etc -cmin -60.
8. Of course, the find command can add multiple options to the query: -a means that both the pre and post conditions must be met, -o means that only one condition is met, so that we can clearly see the filtered items document.
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