Bash--file test, string comparison

File test: Need to add brackets

Whether the-e file exists

Whether the-f file is a normal file

Whether the-D file is a directory

-R file is readable for the current user

-W File Write

-X File Execution

Combination test:

-A and relationship

-O or relationship

! Non-relational

Writing:

If [$A-ge 4-a $A-lt 7]

If [$A-ge 4] && [$A-lt 7]

Greater than or equal to 4 and less than 7

If [$A-ge 4-o $A-lt 4]

If [$A-ge 4] | | [$A-lt 4]

Greater than or equal to 4 or less than 4

Fuzzy matching =~

Integer containing 4 in 1-100

i= ' seq 1 100 '

V=4

[[$I =~ $V]]

Judging file scripts (normal, directory, or other)

Read-p "Please input a file:" N

If [-F $N];then

echo "$N is Putong"

elif [-D $N];then

echo "$N is Mulu"

Else

echo "Bu Cunzai huo Feifa"

Fi

Exercise: Write two numbers to calculate the result of multiplying the two numbers together

#!/bin/bash
#
If [$#-lt 2];then
echo "Qing Xie Chu lia ge Shuzi"
Exit 8
Fi
echo "He wei $[$1+$2]"
echo "Ji Wei $[$1*$2]"

This article is from the "you and I Walk" blog, please be sure to keep this source http://ondali.blog.51cto.com/6650368/1615953

Bash--file test, string comparison