Question

In bash/shell, You need to make a text file. Make a Regular expression that matches any word with 6 or more lower or upper case letters.
Answer:

Answer 1

The regular expression is '[a-zA-Z]{6,}'

The command to match any word with 6 or more lower or upper case letters is $grep -E '[a-zA-Z]{6,}' [filename]

-E argument takes regular expression as extended regular expression.

[a-zA-Z] enumerates a single character that is either a lower case letter or upper case letter. {6,} now selects characters more than 6.

Contents of text file:

O info.txt (-/Deskto Open - 2 info.txt x gsadxafadad 9gsadgaf xfafdad gaalsdax maximum X-mas neon XXX relax aaadsdl ASDDadasd AAFASDGSF sdfAFGEDFG 365654644

Command execution:

pass@ubuntu:-/Desktop$ grep -E '[a-zA-Z]{6,}' info.txt gsadxafadad eggsadgaf xfafdad gaalsdax maximum aaadsd ASDDadasd AAFASDGSF sdfAFGEDFG pass@ubuntu:-/Desktop

The command selects words with more than 6 lower or upper letters.