G'day littlewenwen,

Welcome to the monastery.

One way to do that is with Tie::File: 

$ cat > fred.dat
abcd    123     456     defg
cdefg   23              as
        345     235     
xsd             swe

[download]
$ perl -Mstrict -Mwarnings -e '
    use Tie::File;
    tie my @fred_data, q{Tie::File}, q{fred.dat} or die $!;
    @fred_data = map { s/(^|\t)(?=\t|$)/${1}Missing/g; $_ } @fred_data
+;
    untie @fred_data;
'

[download]
$ cat fred.dat
abcd    123     456     defg
cdefg   23      Missing as
Missing 345     235     Missing
xsd     Missing swe     Missing

[download]

-- Ken

In reply to Re: how to in-place update a dataset? by kcott
in thread how to in-place update a dataset? by littlewenwen

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