How to Replace the value of a column using awk command?

Hi
cat test.txt

H|123|341|567|asfg
D|dfg|trtyy|errt
D|ert|frty|wer

Here I need to replace the third column value with 100 of the first record only and while printing I need to print the full file content also..I am expecting a result like this

H|123|100|567|asfg
D|dfg|trtyy|errt
D|ert|frty|wer

Can some one please help on this

Try:

awk -F"|" -vOFS="|" 'NR==1{$3=100}1' file

Thanks for the quick post ..But its giving me syntax error

awk: syntax error near line 1
awk: bailing out near line

---------- Post updated at 03:29 AM ---------- Previous update was at 03:24 AM ----------

I tried something like this

awk -F"|" -vOFS="|" 'NR==1{$3=100} {print}' file

Its working , but the problem is that its replacing the delimter pipe with space

 
try this..
 
$ nawk -F\| 'NR==1{$3=100;OFS="|";}1' input.txt
H|123|100|567|asfg
D|dfg|trtyy|errt
D|ert|frty|wer