Second week homework

1. What are the file management commands on Linux, their commonly used methods and their related examples?
CP: File copy
CP parameter original target file (clip) target file (clip)
Parameters
I: User interaction, general addition
V: With process
R: Recursive operation, copy folder

[[email protected] tmp]# cp-vi/etc/fstab/tmp//copy Fstab to tmp directory [[email protected] tmp]# CP-RVI/TMP/DIRA/TMP/TEST1/DIRB Copy the Dira directory to the Test1 directory

MV: File movement, renaming
Parameters
I: Tips, user interaction
F: Forced Override

[[email protected] tmp]# mv-i/tmp/fstab/tmp/test/fstab//move fstab to test directory [[email protected] tmp]# mv-i/tmp/dir1/tmp/t EST/DIR1//Move folder Dir1 to test directory [[email protected] tmp]# mv-i/tmp/fstab/tmp/fstab1//rename fstab to Fstab1

RM: File Delete
Parameters
-I: Delete prompt
-F: Force delete
-R: Recursive, delete folder

[[email protected] tmp]# rm-i/tmp/fstab//delete fstab file [[email protected] tmp]# rm-fi/tmp/test1//delete test1 directory

2. Bash's work characteristics the command execution status return value and command line expansion are involved in the content and its sample demonstration.
The command-line deployment is:
~

CD ~//Switch Home directory

{}：

Mkdir-p X/{a,b}//In the creation of A and B subdirectories, respectively, in the X directory

There are two types of execution status return values:
True: denoted by 0

[Email protected] tmp]# echo $?0

False: represented by 1-255 for different error return information

[[email protected] tmp]# Cat/etc/fstabaaacat:/etc/fstabaaa:no such file or Directory[[email protected] tmp]# echo $?1

3. Use the command line expansion function to complete the following exercises:
(1), create/tmp directory: A_c, A_d, B_c, B_d

[[email protected] tmp]# MKDIR-PV {a,b}/{c,d}

(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

[Email protected] tmp]# MKDIR-PV 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}

4, what is the metadata information of the file, what does it mean, how to view it? How to modify timestamp information for a file.
Metadata contains file permissions, size, owning, group, and modification time information

[Email protected] tmp]# ls-l fstab-rw-r--r--. 1 root root 787 00:13 fstab

     timestamp modified with the touch command

[[email protected] tmp]# touch -a -t 201608081022 fstab[[email  PROTECTED] TMP]# TOUCH -M -T 201608091022 FSTAB[[EMAIL PROTECTED] TMP] # stat fstab  file:  ' Fstab '   Size: 787              Blocks: 8           IO Block: 4096   regular fileDevice: fd00h/64768d     Inode: 794200      Links: 1Access:  (0644/-rw-r--r--)   Uid:  (    0/    root)    Gid:  (     0/    root) access: 2016-08-08 10:22:00.000000000 + 0800modify: 2016-08-09 10:22:00.000000000 +0800change: 2016-08-14 10:42:39.743667599  +0800

5, how to define the alias of a command, how to reference the execution result of another command in the command?
Use alias to define an individual name, alias aliasname = Command + option
To use a pipe to reference another command to execute the result

[Email protected] tmp]# CAT/ETC/PASSWD | Grep-e ' ^root\> '--color=auto

6. Display 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.

[[email protected] tmp]# ls/var/l*[[:d igit:]]*[[:lower:]]

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

[Email protected] tmp]# ls/etc/[[:d igit:]]*[^0-9]

8, Show/etc directory, start with a non-letter, followed by a letter and any other arbitrary length of any character file or directory.

[Email protected] tmp]# ls/etc/[^[:alpha:]][[:alpha:]]*

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

[Email protected] tmp]# dirname=$ (date +tfile-%y-%m-%d-%h-%m-%s) [[email protected] tmp]# touch/tmp/$dirname

Or

[[email protected] tmp]# Touch tfile-' Date +%y-%m-%d-%h-%m-%s '

10. 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.

[[email protected] tmp]# mkdir/tmp/mytest1[[email protected] tmp]# cp-irv/etc/p*[^[:d igit:]]/tmp/mytest1/

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

[Email protected] tmp]# mkdir/tmp/mytest2[[email protected] tmp]# Cp-irv/etc/*.d/tmp/mytest2

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

[Email protected] tmp]# mkdir/tmp/mytest3[[email protected] tmp]# cp-iv/etc/[lmn]*.conf/tmp/mytest3/

Second week homework