how to open a file and Search for a string

Posted on 2009-05-19
Last Modified: 2012-05-07
i have a file with some text , when i open and search for some string i am getting errors as below

No such class FILE at line 6, near "open my FIL
syntax error at line 6, near "my FILE,"
Execution of aborted due to compilation errors.

my file contains text as below

didj lmd
bkdfkdfkndkfsnf DCLIENT: lost connection to BE

and below is my code, can u please tell me where the problem is

$koti = "kot.txt";

open my FILE,'>', $koti or die "'$koti' file will not open $!";

while (<TEST>) {

  if ($_ =~ m/DCLIENT: lost connection to BE/g) {

    print "Connection Lost"



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Question by:koti688

Expert Comment

by:Romi Kuntsman
ID: 24420141
Does it work if you put $file instead of FILE?
LVL 19

Expert Comment

by:Kim Ryan
ID: 24420151
FILE is a file handle, not a perl variable. Try this

$koti = "kot.txt";
open FILE,">$koti" or die "'$koti  file will not open $!";
while (<FILE>) {
  if ($_ =~ m/DCLIENT: lost connection to BE/g) {
    print "Connection Lost"

Expert Comment

ID: 24420388
open IN, "myfile.csv" or die "cannot open";
 $flag=1 if(/mystring/);
 print if($flag);


if unix, you can use sed/awk

sed -n '/pattern/,$p' file
awk '/pattern/{f=1}f' file

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LVL 28

Expert Comment

ID: 24421275
>> FILE is a file handle, not a perl variable. Try this

Actually, it's neither.   At this point it's only a bareword.

romi_k was nudging koti688 in the right direction.  Since perl 5.6 it's preferable to use a lexical var for the filehandle instead of a bareword and the 3 arg form of open.

open my $FILE, '>', $koti or die "'$koti' file will not open $!";

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Accepted Solution

vikaskhoria earned 500 total points
ID: 24431460
There are two issue with the code segment you have pasted:

1. Using my for FILE , my is not required here. That is giving the error.
2. The other one is a programing error, you are declaring the file-handle as FILE and using TEST in while loop to read data.

So these two line should look like this:

open FILE,'>', $koti or die "'$koti' file will not open $!";
while (<FILE>) {


Expert Comment

ID: 24646757
Try this:

open (FILE,"kot.txt") or die "kot.txt file will not open $!";
while (<FILE>) {
  if ($_=~m/DCLIENT: lost connection to BE/) {
    print "Connection Lost";
  close FILE;

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