This is the 8th day of my participation in Gwen Challenge

8. Search for lookup classes

8.1 the find

The basic grammar

Find [option]Copy the code

Option to show

options function
-name< Query Mode > Finds files according to the specified file name lookup mode
-user< user name > Find all files belonging to the specified user name
-size< file size > Find files based on the specified file size, in:

B — Block (512 bytes)

C – byte

W — word (2 bytes)

K — kilobytes

M — megabytes

G — gigabytes		 
[root@hadoop1 test]# find./ -name b.testt [root@hadoop1 test]# find./ -user test123 ## +n > -n < n equal to [root@hadoop1 test]# find ./ -size -200cCopy the code

8.2 locate

The Locate directive quickly locates a given file using the LOCATE database of all file names and paths established in the system. The Locate command does not need to traverse the entire file system, resulting in faster queries. To ensure the accuracy of query results, administrators must periodically update locate time.

The basic grammar

Locate search fileCopy the code

Since the locate command is based on the database query, the first run must use the updatedb command to create the locate database/TMP directory

[root@hadoop1 ~]# updatedb
[root@hadoop1 ~]# locate .txt
Copy the code

8.3 the grep and |

Pipeline operators, “|”, said the previous command processing results of the output is passed to the back of the command processor

The basic grammar

The grep option finds the content source fileCopy the code

Option to show

options function
-n Displays the matching line and line number 
[root@hadoop1 test]# grep -n abc b.txt
[root@hadoop1 test]# ll | grep b
Copy the code

9. Compression and decompression classes

9.1 gzip/gunzip

The basic grammar

Gz gunzip file. Gz (Decompress the file)Copy the code

Tips (1) Compress only files but not directories. (2) Do not retain original files. (3) Multiple compressed packages are generated when multiple files are created at the same time

[root@hadoop1 test]# gzip b.txt
[root@hadoop1 test]# gunzip b.txt.gz
Copy the code

9.2 zip/unzip

The basic grammar

Zip Contents to be compressed (Function description: commands to compress files and directories) unzip [option] XXx. zip (Function description: Decompresses files)Copy the code

Option to show

Zip options function
-r Compressed directory
Unzip options function
– d < directory > Specify a directory for storing decompressed files 
[root@hadoop1 test]# zip -r a.zip a.txt ./a
[root@hadoop1 test]# unzip a.zip
[root@hadoop1 test]# unzip a.zip -d ./a
Copy the code

9.3 the tar

The basic grammar

Gz Contents to be packed (Function description: Package directory, compressed file format.tar.gz)Copy the code

Option to show

options function
-c Generates a.tar package file
-v Display details
-f Specifies the compressed file name
-z Pack and compress simultaneously
-x Unpack the. Tar file
-C Decompress to the specified directory 
[root@hadoop1 test]# tar -zcvf b.tar.gz b.txt
[root@hadoop1 test]# tar -zxvf b.tar.gz -C ./bb
[root@hadoop1 test]# tar -zxvf b.tar.gz
Copy the code

10. Disk partition classes

10.1 df

The basic grammar

Df option (Function description: Lists the total disk usage of the file system and checks the disk space usage of the file system)Copy the code

Option to show

options function
-h Self-display in human-readable GBytes, MBytes, KBytes, etc 
[root@hadoop1 test]# df file system 1K- Block used Available Used % mount point devtmpfs 3993812 0 3993812 0% /dev//dev/vda1 41152736 21538252 17501000 56% / [root@hadoop1 test]# df -h File system capacity used Available Used % mount point devtmpfs 3.9g 0 3.9g 0% /dev........Copy the code

10.2 fdisk

The basic grammar

Fdisk -l (Function description: View disk partition details)Copy the code

Option to show

options function
-l Displays the partition list of all hard drives

Tip: This command can be used only when the root user is running it

Linux partition Device: partition sequence Boot: Boot Start: starts from magnetic column X End: ends from magnetic column Y Blocks: capacity Id: Id of the partition type System: indicates the partition typeCopy the code
[root@hadoop1 test]# fdisk -l /dev/vda: Units = Sector of 1 x 512 = 512 bytes Sector size (logical/physical) : 512 bytes / 512 bytes I/O size (minimum/Best) : 512 bytes / 512 bytes Disk label type: DOS Disk Identifier: 0x000256f2 Device Boot Start End Blocks Id System /dev/vda1 * 2048 83886079 41942016 83 LinuxCopy the code

10.3 LSBLK

The basic grammar

LSBLK (View device mounting information)Copy the code

Option to show

options function
-f View detailed device mounting information and display file system information 
[root@hadoop1 test]# lsblk-f NAME FSTYPE LABEL UUID MOUNTPOINT vda ├ ─vda1 ext4 de91b9Ee-777-4a74-a22D-41669AC18c4a /Copy the code

10.4 Mount /umount Mounting/Unmounting

The basic grammar

Mount [-t vfstype] [-o options] Device dir (Mount device) umount Device file name or mount point (mount device)Copy the code

Parameters that

parameter function
-t vfstype Specifies the type of file system. Mount automatically selects the correct type. Common types are:

CD or CD image: iso9660

DOS FAT16 file system: MSDOS

Windows 9X FAT32 file system: VFAT

Windows NT NTFS file system: NTFS

Mount Windows file network sharing: SMBFS

UNIX(LINUX) File network sharing: NFS
-o options This parameter describes the attaching mode of devices or files. Common parameters are:

Loop: Used to attach a file to the system as a disk partition

Ro: The device is mounted in read-only mode

Rw: Connects to the device in read/write mode

Iocharset: specifies the character set used to access a file system
device Equipment to be mounted
dir The mount point of the device on the system