3.0-vim editor and bash condition test

Multi-file Mode:

Vim FILE1 FILE2 FILE3 ...

: Next Next

:p Rev A previous

: First One

: Last One

: Wall Save All

: Qall Quit all

Window-delimited mode:

Vim-o|-o FILE1 FILE2 ...

-O: Horizontal split

-O: Vertical split

Switch between windows: Ctrl+w then arrow (arrow: Flag on keyboard)

Single File Window segmentation:

Ctrl+w,s:split Horizontal Split

Ctrl+w,v:vertical Vertical Segmentation

Customizing the working characteristics of vim:

Configuration file: Permanently valid

Global:/ETC/VIMRC

Personal: ~/.VIMRC

Last line: The current VIM process is valid

(1) Line number

Display: Set number, abbreviated as: Set Nu

Cancel display: Set Nonumber, abbreviated as: Set Nonu

(2) Bracket matching (automatic matching of left and right brackets in programming)

Match: Set Showmatch, abbreviated as: Set SM

Cancel match: Set Noshowmatch, abbreviated as: Set NOSM

(3) Auto Indent

Enable: Set AI

Disabled: Set Noai

(4) Highlight Search

Enabled: Set Hlsearch

Disabled: Set Nohlsearch

(5) syntax highlighting

Enabled: Syntax on

Disabled: Syntax off

(6) Ignore character case

Enable: Set IC

Disabled: Set Noic

Get help

: Help

: Help Subject

Problem: How to Set tab indent to 4 characters

Practice:

1. Copy the/etc/rc.d/init.d/functions file to the/tmp directory: Replace the/etc/sysconfig/init in the/tmp/functions file with the/var/log

2. Delete the # number at the beginning of all lines in the/tmp/functions file that begin with # and have at least one white space character after #

#hello

# Hello (Remove the # character with a space after this #)

Bash condition test:

Test method:

Test EXPRESSION

[EXPRESSION]

[[EXPRESSION]]

To test the category of an expression:

Numerical comparison

String test

File test

File test

Existence test:

-A FILE (same-E, rarely used)

-e File: Document existence test, existence is true, there is no false

Presence and category testing:

-B File: Exists and is a block device file

-C file: exists and is a character device file

-D file: Exists and is a catalog file

-F file: exists and is a normal file

-H file or-L file: exists and is a symbolic link file

-P file: exists and is a named pipe file

-S file: exists and is a socket file

File permission test:

-R FILE: exists and is readable

-W FILE: exists and is writable

-X FILE: exists and is executable

File Special Permissions Test:

-G FILE: Exists and has Sgid permissions

-U FILE: Exists and has suid permissions

-K FILE: Exists and has sticky permissions

File size test:

-S FILE: exists and is not empty

Whether the file is open:

-T FD:FD indicates whether the file descriptor is open and related to a terminal

-N File: Files are automatically modified after they have been read for the last time

-O File: Whether the current active user is a file owner

-G file: whether the current active user is a group of files

Binocular test:

File1-ef whether File2:file1 and FILE2 point to the same inode on the same device

File1-nt File2:file1 is new to FILE2

File1-ot File2:file1 is older than FILE2

Combination Test conditions:

Logical operation:

The first way:

COMMAND1 && COMMAND2

COMMAND1 | | COMMAND2

! COMMAND

For example: [-E file] && [-R File] files exist and are readable

Note: When doing a file test, be sure to pay attention to whether it is root or ordinary user, if it is root permission to judge there will be problems

The second way:

Expression1-a EXPRESSION2

Expression1-o EXPRESSION2

EXPRESSION

You must use the test command to

# [-Z $hostName-o $hostName = = Bogon] && hostName test

# [-f/bin/cat-a-x/bin/cat] && cat/etc/fstab

3.0-vim editor and bash condition test