How Can I avoid a Indefinite Loop While Searching a string from a no of files - perl

Question

In my below program, I was trying to search a string from no of files In a folder but output Is printing in continuous manner rather than stopping after required search. Can some one pls help to point out the error ?
i.e. I am trying to Search the string "VoLTE SIPTX: [SIPTX-SIP] ==> REGISTER" from #files but I am not getting the desired output but I am getting repetitive output of my strings.
# #!/usr/bin/perl
# use strict;
use warnings;
&IMS_Compare_Message();
sub IMS_Compare_Message
{
print "Entering the value i.e. the IMS Message to compare with";
my $value = '';
my $choice = '';
my $loop = '';
print "\nThe script path & name is $0\n";
print "\nPlease enter desired number to select any of the following
(1) Start Comparing REGISTER message !!
(2) Start Comparing SUBSCRIBE message
(3) Start Comparing INVITE message \n";
$value = <STDIN>;
if ($value == 1 )
{
print "\n Start Comparing REGISTER message\n\n";
$IMS_Message = "VoLTE SIPTX: [SIPTX-SIP] ==> REGISTER";
#chomp ($IMS_Message);
}
elsif ($value == 2)
{
print "\n SUBSCRIBE message Flow\n\n";
}
elsif ($value == 3)
{
print "\n INVITE message Flow\n\n";
}
else
{
print "\nThe input is not valid!\n";
print "\nDo you want to continue selecting a Automation Mode again (Y or N)?\n";
$choice = <STDIN>;
if( $choice =~ /[Yy]/) {
test_loop();
} else {
exit;
}
}
my $kw = "$IMS_Message";
my #files = grep {-f} (<*main_log>);
foreach my $file (#files)
{
open(my $fh, '<', $file) or die $!;
my #content = <$fh>;
close($fh);
my $l = 0;
$search = chomp ($kw);
#my $search = quotemeta($kw);
foreach (#content)
{ # go through every line for this keyword
$l++;
if (/$search/)
{
printf 'Found keyword %s in file %s, line %d:%s'.$/, $kw, $file, $l, $_
}
}
}
}
After Modificaiton
# #!/usr/bin/perl
use strict;
use warnings;
print "Entering the value i.e. the IMS Message to compare with";
my $value = '';
my $choice = '';
my $loop = '';
my $IMS_Message = '';
my $search = '';
my $kw = '';
print "\nThe script path & name is $0\n";
print "\nPlease enter desired number to select any of the following
(1) Start Comparing REGISTER message !!
(2) Start Comparing SUBSCRIBE message
(3) Start Comparing INVITE message \n";
$value = <STDIN>;
if ($value == 1 )
{
print "\n Start Comparing REGISTER message\n\n";
$IMS_Message = "VoLTE SIPTX: [SIPTX-SIP] ==> REGISTER";
#chomp ($IMS_Message);
}
elsif ($value == 2)
{
print "\n SUBSCRIBE message Flow\n\n";
}
elsif ($value == 3)
{
print "\n INVITE message Flow\n\n";
}
else
{
print "\nThe input is not valid!\n";
print "\nDo you want to continue selecting a Automation Mode again (Y or N)?\n";
$choice = <STDIN>;
if( $choice eq /[Yy]/) {
test_loop();
} else {
exit;
}
$kw = $IMS_Message;
$search = qr/\Q$kw/;
for my $file ( grep { -f } glob '*main_log' ) {
open my $fh, '<', $file or die qq{Unable to open "$file" for input: $!};
while ( <$fh> ) {
if ( /$search/ ) {
printf "Found keyword %s in file %s, line %d: %s\n", $kw, $file, $., $_;
last;
}
}
}
}

Answer 1

Here are some observations on your code
Your approach to debugging appears to be to try things at random to see if they work. It would be far more fruitful to add diagnostic print statements so that you can compare variables' actual values with what you expect
Error and warning messages are useful information, and it is foolish to comment out use strict to make them go away
Don't call subroutines with an ampersand &. That hasn't been best practice for twenty years now
Lay your code out tidily and cinsistently, so that both you and any people you ask for help can read it easily. As it stands it is impossible to tell where blocks start and end without counting brace characters {...}
Variables should be declared with my as close as possible to their first point of use, and not all at once at the top of the file or subroutine
chomp is necessary only for strings that have been read from the terminal or from a file. It returns the number of characters removed, not the trimmed string
if( $choice =~ /[Yy]/ ) { ... } will check only whether the string contains a Y, so if the operator enters MARRY ME! it will return true. You should use string equality eq to check whether a single Y character has been typed
You shouldn't put scalar variables alone inside double quotes. At best it will make no difference, and just add noise to your code; at worst it will completely change the value of the variable. Just my $kw = $IMS_Message is correct
Unless you require non-sequential access to the contents of a file, it is best to use a while loop to read and process it line by line, rather than read the whole thing into an array and process each element of the array. This also allows you to use the built-in line number variable $. instead of implementing your own $l
The main problem is that you have derived $search from the result of chomp $kw, which sets $search to the number of characters removed by chomp. This is always zero because $kw is a copy of $IMS_Message, which has no newline at the end. That means you are checking all the lines of every file for the character 0, and not for the message that you intended. The correct way is my $search = quotemeta($kw) which you had in place but have commented out, presumably as a result of your policy of "debugging by guesswork"
Fixing these things, your code should look something like this
my $search = qr/\Q$kw/;
for my $file ( grep { -f } glob '*main_log' ) {
open my $fh, '<', $file or die qq{Unable to open "$file" for input: $!};
while ( <$fh> ) {
if ( /$search/ ) {
printf "Found keyword %s in file %s, line %d: %s\n", $kw, $file, $., $_;
last;
}
}
}