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perl grep function

FILE
short@shortcasper-laptop:more Daccount.t | tail -5

USERID ACCOUNTNUM
badam4 w7897C Dru100 dmu107g
bfdam4 w90581 Dru1720 dmu118f
bhdam5 w90781C Dru120 dmu118f
bsdam7 w65665 Dru90 dmu118d
bwdams w665C Dru90 dmu118d

short@casper-laptop: more Duser.txt | tail -5
FILE2
USERID CLIENTID
badam4 f#OI[S[) 0 0 0 0 0 -1.000 -1.000 -1.000 -1 450640
bfdam4 J|T;[y& 0 0 0 0 0 -1.000 -1.000 -1.000 -1 246267
bhdam5 l+X7Kp$+ 0 0 0 0 0 -1.000 -1.000 -1.000 -1 363076
bsdam7 x([=KNW$ 0 0 0 0 0 -1.000 -1.000 -1.000 -1 476250
bwdams w".t-R 0 0 0 0 0 -1.000 -1.000 -1.000 -1 21528

So i have the two files above - file and file2. notice how the USERID is the same in the two files. what i have to do is get the USERID out of FILE1 and the grep the userid out of FILE2 to get the matching CLIENTID.

ultimately i need to print out the USERID , ACCOUNTNUM and CLIENTID in one line. But for now with the script below, all I get is the one CLIENTID from the FILE2. I have been working on this all night and can't figure it out. The results should be a whole list of CLIENTID's, not just one value - namely the last value. I be the answer is really simple.

1 #!/usr/bin/perl -w
2 open FILE1 , "/home/shortcasper/Daccount.txt" or die "Could not open $!";
3 open FILE2 , "/home/shortcasper/Duser.txt" or die "Could not open $!";
4 my @arry1 = <FILE1>;
5 my @arry2 = <FILE2>;
6 my $line = 0 ;
7 my $foo = 0;
8 foreach $line( @arry1) {
9 ($userid, $acct, $CCP, $creditman) = split /\s+/, $line;
10 @foo = grep(/$userid/, @arry2);
11 }
12
13
14
15 foreach $foo(@foo){
16 ($userid2, $you, $wnum, $zoo, $suc, $dig, $crag, $tip, $ger, $nin, $waw, $clientid) = split /\s+/, $foo;
17 print "$clientid\n" ;
18 sleep 1;
19 }
20

results is

21528 (the CLIENTID in that last line of FILE2 - that is it. it should be the whole list. )

Does it have to be perl?

Code:

awk 'FNR == NR{a=$1;$1="";list[a] = $0;next}{if($1 in list)print $1,list[$1],$2}' file file2

Please also use [code][/code] tags to help make code more readable.

Since the second foreach loop only acts on the last line of the FILE2 i think that i need to nest the second foreach loop better so it iterates over each line of FILE2

Code:

 #!/usr/bin/perl -w

 open FILE1 , "/home/shortcasper/Daccount.txt" or die "Could not open $!";

 open FILE2 , "/home/shortcasper/Duser.txt" or die "Could not open $!";

 my @arry1 = <FILE1>;

 my @arry2 = <FILE2>;

 my $line = 0 ;

 my $foo = 0;

 foreach $line( @arry1) {

    ($userid, $acct, $CCP, $creditman) = split /\s+/, $line;

    @foo = grep(/$userid/, @arry2);

      }



 foreach $foo(@foo){

 ($userid2, $you, $wnum, $zoo, $suc, $dig, $crag, $tip, $ger, $nin, $waw, $clientid) = split /\s+/, $foo;

 print "$clientid\n" ;

 sleep 1;

 }

Had a play ... this seems to work:

Code:

#!/usr/bin/perl



open FILE1 , "f1" or die "Could not open $!";

open FILE2 , "f2" or die "Could not open $!";



my @arry1 = <FILE1>;

my @arry2 = <FILE2>;



foreach $line( @arry1) {

        next if $line =~ /USERID/;

        ($userid, $acct, $CCP, $creditman) = split /\s+/, $line;

        @foo = grep(/$userid/, @arry2);

        ($userid2, $you, $wnum, $zoo, $suc, $dig, $crag, $tip, $ger, $nin, $waw, $clientid) = split /\s+/, $foo[-1];

        print "$clientid\n" ;

        sleep 1;

}

nice... yeah it works.

it also works when i add foreach loop after the grep

Code:

@foo = grep(/$userid/, @arry2);

        foreach $foo(@foo){

        ($userid2, $you, $wnum, $zoo, $suc, $dig, $crag, $tip, $ger, $nin, $waw, $clientid) = split /\s+/, $foo[-1];

        print "$userid, $acct, $clientid\n" ;

        }

Even when i tag on a print "$userid, $acct, $clientid\n"; - it still works -
it grabs all the values from both arrays perfectly.

what is the foo[-1] do? the script will run without it. yet i am hesitant to take it off.

It doesn't work for me because as you can see my code does not loop through the @foo array like yours does, but unless there is a chance you will return more than one line
the foreach is not required. The foo[-1] returns the last element in the array. Could have easily been a 0 if only one item is returned.

In general can I suggest you change the start to

Code:

#!/usr/bin/perl -w

use strict;

and do a

Code:

perl -wc file.pl

and deal with any errors/warnings before running a perl prog.
Also, using scalars and arrays (or hashes) with the same name (eg 'foo') makes the code hard to read & can easily lead to obscure errors.