Hi siva.snimmaka,
If your intention is to pick out "abcd_efgh-1.2.3" from "abcd_efgh-1.2.3-hjik-3.4.5.tar.gz", you can used 

$_ = 'abcd_efgh-1.2.3-hjik-3.4.5.tar.gz';
  print $1 if /(.+?)-[a-z].+?/i; ## prints abcd_efgh-1.2.3

[download]
or any of the previous solutions.
However, if your intention is to "match" only "abcd_efgh-1.2.3" in data that has several lines of similar strings, then I will go with kcot's solution.
Please also check up perlrequick and perlre if you have not.

If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

In reply to Re: Need help on regexp by 2teez
in thread Need help on regexp by siva.snimmaka

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