/:ID\s(\d*).*:P_ID\s(\d*)/

You can then refer to the matches using $1 and $2 respectively.

Hope this helps.
-- Foxcub

Thanx again!:) Does the snippet work if there are more than one ID/P_ID in an array element?

If you want to act on more than one id then try

while ($arrayElement =~ /:ID\s(\d*).*:P_ID\s(\d*)/g ) {
    print $1,$2,"\n"; # just an example
}
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The /g gets all matches of the regex, so the captured bit ($1,$2) will be updated for each match in the while loop.

For that, you'd want to use the global (/g) modifier on the end of your regex, and use the regex in a list context:
@ids = m/:ID\s\d*/g

You'll need to do another regex to pull the P_IDs,
@p_ids = m/:P_ID\s\d*/g,
and you won't be able to use backreferencing to ditch the ":ID " part.

For that, I guess you could use another regex, or, if the data is regular, something like:
for $i (0..$#ids) {$ids[Ģi] = substr ($ids[$i], 4);}

No, you'll have to think a little here.

Hotshot

while(<>){
my ($id, $user_name, $p_id, $password) = split ':';
#do stuff to the stuff in $id and $p_id
}
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thor

/ID\s+(\d+).+P_ID\s+(\d+)/;
$id = $1;
$pid = $2
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