Question

In: Computer Science

this is bash scripting. a. Explain the difference between grep and egrep? b. Write a command...

this is bash scripting.

a. Explain the difference between grep and egrep?

b. Write a command to list files where third letter is x or y?

c. Write command to remove array element with id 5

Expert Solution

Answer a)
grep stands for Global Regular Expressions Print but egrep stands for Extended Global Regular Expressions Print

When we use grep for pattern search for the symbols cannot be done directly we have to use the backslash but in egrep the symbols are the meta characters which we can use directly without backslash.

grep -E is same as egrep

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Answer b)

ls ??[xy]*

here ?? means any character for the first two characters and for the third letter [xy] means either x or y then * means any character after x or y.

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Answer c)

unset arr1[5]

By the unset command we can remove the array element in a shell script.

venereology answered 1 year ago

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