Topics about some directives for Linux

/proc/cpuinfo

var/log/dmesg -n1

Question 3 & 4: The instruction is free. The result has several columns, where total is the total amount of memory configured, and free is how much memory is currently available.

It is also the same as using cat proc meminfo.

proc/diskstats

proc/stat

Since the Linux system is different, each machine is different, so it is recommended that you check it on your own machine.

1. cp command, function copy, parameters are as follows:

A: Copy the properties of the file together.

p: Replicated along with the file's attributes, instead of using the default method, similar to -a, often used for backups.

i: If the target file already exists, the target file will be asked to perform the operation when overwriting.

r: recursive continuous replication, used for the replication behavior of directories.

u: The target file is copied only when there is a difference between the target file and the source file.

2. The rm command is used to delete, and the parameter is:

f: That's what force means, ignore non-existent files, and no warning message will appear.

i: Interactive mode, the user will be asked if they want to take action before deleting.

r: Recursive deletion, most commonly used for directory deletion, is a very dangerous parameter.

3. The MV command is used to move files

f:force coercion, if the target file already exists, it will not be asked and will be overwritten.

i: If the target file already exists, it will ask if it is overwritten.

u: If the target file already exists and is newer than the target file, it will be updated.

4. pwd command, which is used to view the complete path of the "current working directory".

pwd-p shows the actual path instead of using the link path; PWD shows the connection path.

5. rmdir command to delete the directory:

rmdir [option].Directory.

p: Recursively deletes the directory dirname, and when the parent directory of the subdirectory is deleted and the parent directory is empty, it is also deleted. If the entire path is deleted or part of the path is left for some reason, the system displays the appropriate information on the standard output.

v: verbose shows the command execution process.

Through the expainshell explanation translation, we can know that Change the Working Directory is what CD means in the Linux command line, i.e., change the workspace directory.

2: Brother Bird's Linux Private Cuisine Basic Learning.

Or for. My knowledge of the above information is only in the following areas:

1:d indicates that this is a folder - and the one that starts indicates that it is a file.

2: d and - after the current user's permissions are r (read) w (write) x (executable).

In the subsequent gradual study, I will add some knowledge points to this part.

After running the following command, you will see the created file in the test2 directory and the file content is the same as test1"1"

Examples:

Execute the following commands in order.

The meaning of the -r command in the example is:

explainshell: cp -r

r, -r, -recursive

copy directories recursively

i.e. recursion operations involving directories (folders) need to be recursive.

When you're done with the example, you return to the sibling directory of test1 and you'll see the test2 directory.

test2 has the same file as in the test1 directory.

When you are done with the operation in the example, it is equivalent to cutting the test1 directory to the test2 folder and renaming it.

After the tree command is executed, you can observe that the directory structure under the test directory is as follows