My awk program to change spaces into tabs doesn't work

Question

How to write a shell script which uses awk to read in the data file students.txt and output the data in the tabbed format as shown:

Surname Forename MSc Stream Date of Birth
Smith John IT 15.01.1986
Taylor Susan IT 04.05.1987
Thomas Steve MIT 19.04.1986

• Do not worry if tabbed columns don’t line up.

• The distance between each of (Surname, Forename, MSc Stream and Date of Birth) column is one tab.

Question:

Why this code bellow doesn't work for me?

awk 'BEGIN {IFS=" "} {OFS="\t"} {print $1,$2,$3,$4}' students.txt

Answer 1

awk '{$1=$1}1' OFS="\t" students.txt

Proof of Concept

$ awk '{$1=$1}1' OFS="\t" students.txt
Surname Forename        MSc     Stream  Date    of      Birth
Smith   John    IT      15.01.1986
Taylor  Susan   IT      04.05.1987
Thomas  Steve   MIT     19.04.1986

Explanation

The reason it didn't work is because awk requires one of the fields to be changed before it applies the new output field separator. The workaround for this defect (IMHO) is to just set a field to itself, hence the $1=$1

---

For this simple type of change, you're better off using tr or sed

tr ' ' '\t' < students.txt
sed 's/ /\t/g' students.txt

Answer 2

This is wrong:

awk 'BEGIN {IFS=" "} {OFS="\t"} {print $1,$2,$3,$4}' students.txt

because you're setting OFS too late (not in the BEGIN block). Do this:

awk 'BEGIN {OFS="\t"} {print $1,$2,$3,$4}' students.txt

Don't forget to change your header to have 4 space-separated fields:

Surname Forename MSc_Stream Date_of_Birth