You're using the wrong operator. You are assigning to $F[0] instead of using regex binding.

perl -pi -w -lane '$F[0] =~ s/AAA/BB/;' *.txt

[download]

could work.

In reply to Re: In-place search and replace confined to a specific column by Corion
in thread In-place search and replace confined to a specific column by Anonymous Monk

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