If I understand your problem correctly the line of code you want is @newArray = (map {tr/_/./; $_} @array):

my @newArray =
  (
  map
    {my ($lhs, $rhs) = /(.*?)=(.*)/; $lhs =~ tr/_/./; "$lhs=$rhs"}
    @array
  );

[download]
use strict;
use warnings;

my @array =
  qw(
    oracle_hst_sid=hsta
    oracle_sid=sdpa
    oracle_home=/oracle/product_1/10.2.0
    sdp_home=/oracle/oracle8
    );

my @newArray =
  (
  map
    {my ($lhs, $rhs) = /(.*?)=(.*)/; $lhs =~ tr/_/./; "$lhs=$rhs"}
    @array
  );

print join "\n", @newArray;

[download]
Update: altered to only alter text to the left of = per pjf's suggestion

Perl is Huffman encoded by design.

In reply to Re: substitution in a string by GrandFather
in thread substitution in a string by s_gaurav1091

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