File wildcard

I. document wildcards

Wildcards are mainly used to find matching characters by setting certain conditions.

* match any character, including 0

? Match any single character

~ username: matches the home directory of username

Cp / root/file1 ~ tom/ #: copy the file1 file to the tom user's home directory

~ match to the current home directory

[abc] matches to any letter in abc

[^ abc] matches to any character except abc

[0-9] matches any number between 0-9

[amurz] matches any letter between aAbBcC-z

[Amurz] matches any letter between AbBcC-zZ

[: alpha:] matches any letter

[: digit:] matches any number

[: alnum:] matches any letter or number

[: upper:] matches any uppercase letter

[: lower:] matches any lowercase character

[: punct:] matches any symbol

[: space:] matches any space

Exercise:

1. Display all files or directories in the / var directory that begin with I, end with a lowercase letter, and have at least one digit in the middle

Ls / var/I* [1-9] * [[: lower:]]

2. Display files or directories under the / etc/ directory that begin with any number and end with a non-number

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

3. Display files or directories in the / etc/ directory that begin with a non-letter, followed by a letter and any other characters of any length.

Ls / etc/ [^ [: alpha:]] [: alpha:] *

4. Display all files or directories under the / etc/ directory that begin with m and end with a non-numeric end

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

5. Show all files or directories ending in .d in the / etc/ directory

Ls / etc/*.d

6. Show all files or directories in the / etc/ directory that end with .conf and begin with mreco ndir r rep.

Ls / etc/ [mnrp] * .conf