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Old February 22nd, 2006, 10:22 AM
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Default search a file for every element in array and appen

Hi All,

Can you please tell me how to search in a txt file for each array element.

If my array contains 3 elements say io, new folder,po,new folder(2).
i want to check these elements in a text file one by one if it exists then exit the loop if it does not exist then append the elements to the text file.

i tried the below code but i am certain only the first half is correct and requires some help for the second half

chdir('D:\pp') or die "$!";
opendir(DIR,'.') or die "$!";

@folders = grep (-d && !/^\.+$/, readdir(DIR));

print "before sorting\n";
print "$_\n" for @folders;

@sortf = sort(@folders);

print "after sorting\n";
print "$_\n" for @sortf;

print $cnt;

open(FILE,"+>>DB.txt") or die "$!";

while ( <FILE> )
 $myfile = $myfile . $_;


foreach my $dirs (@sortf) {
 @times= grep(/$dirs/,$myfile);

#i am not sure how to append the non existing entries to the file with the output of grep



Can any one let me know the right way of doing this.

Thanks in advance.

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Old March 6th, 2006, 05:36 PM
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To open a text file and check for every element in an array within the file:

 - open the file
 - read it into an array
 - close the file
 - for each element of the file_array, grep for each element of the targets_array

You'll need to understand map and grep to get this:

#!/usr/bin/perl -w
# look for elements of array @targets in file $file
use strict;

my @targets=qw|target1 target2 target3|;
my $file = 'myfile';

open (INPUT, $file);
my @file_lines = <INPUT>;
close INPUT;

my @found_lines = map { my $tg=$_;
                        grep {/$tg/x} @targets } @file_lines ;

print join ", ",@found_lines;
print "\n";


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