Use awk to update only 2nd line


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# 1  
Use awk to update only 2nd line

I have a file and need to update the specific position on line two. I tried to use this solution under the post "Awk command to replace specific position characters"


But need a way to just limit to update the line 2 and not every line on the file.

Code:
awk 'function repl(s,f,t,v) { return substr(s,1,f-1) sprintf("%-*s", t-f+1, v) substr(s,t+1) } { a=repl($0,37,46,"0000000002")   print a }' infile

Can someone help.

Last edited by vgersh99; 11-21-2018 at 11:48 AM.. Reason: Code tags, please!
# 2  
Code:
awk 'function repl(s,f,t,v) { return substr(s,1,f-1)  sprintf("%-*s", t-f+1, v) substr(s,t+1) } FNR==2{  a=repl($0,37,46,"0000000002")   print a }' infile

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