Second week homework

1. Linux What are the file management class commands on, their common usage methods, and their associated example demos.

Answer: CP Usage:

CP [OPTION] ... [-T] SOURCE destcp [OPTION] ... SOURCE ... DIRECTORYCP [OPTION] ...-t DIRECTORY SOURCE ...

Common options:

- I. : Interactive

- R ,-R: recursively replicate directories and all internal content:

-A : Archive, equivalent to-DR--preserv=all

- D :--no-dereference--preserv=links

--preserve[=attr_list]

Default defaults include properties: Mode, ownership, timestamps

If Use = contains the following attribute, the corresponding property is included

mode: Permissions

Ownership: belong to the group of main genera

Timestamp: time Stamp

links : Link Properties

xattr: Extended Properties

Context : Security Context

All  

- P : equivalent to--preserve

- v :--verbose

- F : Force

RM Usage:

RM [OPTION] ... FILE ...

Common options

- I. : Interactive

- R : Delete directory files recursively

- F : Force Delete without confirmation

Example: rm-rf/tmp/*

MV Usage:

MV SOURCE ... DEST

If there are multiple sources of movement, then the target must be a directory

Common options:

- I. : Interactive

- F : Force

Default mv= "Mv-i"

2. Bash the command execution status return value and command-line expansion are involved in the work feature and its example demonstration.

A: The command execution success status return value is 0, the command execution failure status return value is 1~255;

Bash of the command line expand content:

~ : Expand to the user's home directory

~username : Expand the home directory for the specified user

{}: Can host a comma-delimited list and expand it to multiple paths

/tmp/{a,b} =/tmp/a,/tmp/b/tmp/{tom,jerry}/hi =/tmp/tom/hi,/tmp/jerry/hi

3 , use the command-line deployment feature to complete the following exercises:

(1) , creating the/tmp directory: A_c, A_d, B_c, B_d

mkdir {AB}_{CD}

(2) , create the/tmp/mylinux directory:

mylinux/

├──bin

├──boot

│└──grub

├──dev

├──etc

│├──rc.d

││└──init.d

│└──sysconfig

│└──network-scripts

├──lib

│└──modules

├──lib64

├──proc

├──sbin

├──sys

├──tmp

├──usr

│└──local

│├──bin

│└──sbin

└──var

├──lock

├──log

└──run

Mkdir-p/tmp/mylinux/{bin,boot/grub,dev,etc/{rc.d/init.d,sysconfig/network-scripts},lib/modules,lib64,proc,sbin , Sys,tmp,usr/local/{bin,sbin},var,lock,log,run}

3. What are the metadata information for a file, what does it mean, and how to view it? How to modify timestamp information for a file.

A: Stat can view the metadata information of a file, including the location, size, block size, file type, save location, inode location, access rights, contextual information, Atime, Mtime, CTime, and other information.

Use touch to modify the timestamp information for a file.

Touch Usage:

Touch[option] ... FILE ...

Common options

-A : Change only atime

- M : Change only mtime

- T STAMP : Change to the appropriate timestamp

[[Cc]yy] MMDDHHMM[.SS]

- C : If the file does not exist, it is not created and changes its timestamp if it exists

4. How do I define an alias for a command, and how do I refer to the execution result of another command in a command?

A: Define command aliases using the command alias:

ALIAS[-P] [Name[=value] ...]

The execution result method that references another command in a command can have the following two methods depending on the scenario:

Method 1: Use management |

Cat/etc/fstab |wc-l

Method 2: Use the inverse quotation marks

mkdir/tmp/tfile-' Date +%f-%h-%m-%s '

5. displays all files or directories in the/var directory that start with L, end with a lowercase letter, and have at least one digit (can have other characters) appear in the middle.

ls-d/var/1*[0-9]*[[:lower:]]

6. displays files or directories that start with any number in the/etc directory and end with a non-numeric number.

Ls-d/etc/[0-9]*[^0-9]

7. displays a file or directory that starts with a non-letter, followed by a letter and any character of any length, in the/etc directory.

Ls-d/etc/[^a-za-z][[:alpha:]]*

8. in the/tmp directory, create a file that begins with Tfile, followed by the current date and time, with a filename such as tfile-2016-08-06-09-32-22.

mkdir/tmp/tfile-' Date +%f-%h-%m-%s '

9. copy all the files or directories in the/etc directory to the/tmp/mytest1 directory that begin with P and do not end with a number.

Cp-a/etc/p*[^0-9]/tmp/mytest1

10. Copy all files or directories ending with. D in the/etc directory into the/tmp/mytest2 directory.

Cp-a/etc/*.d/tmp/mytest2

A , copy all files in the/etc/directory that begin with L or M or N and end with. conf to the/TMP/MYTEST3 directory.

Cp-a/etc/[lmn]*.conf/tmp/mytest3

Second week homework