I am looking for a simple way to test if a file does not contain a
string. This is on a linux box.

if myfile does not contain mystring {
#do_something;
}

The file is basically a list of names and I want to test that a
certain name is not in there. Is there an easy way to do that?

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--001485f0a01e6b4d89049d83d75d
Content-Type: text/plain; charset=UTF-8

# Untested
use strict;
use warnings;

open my $fh, '<', my_file;
while(<$fh>){
if ($_ !~ /my_string/) {
# Do something
}
}

The other way would be on shell -

# Untested
grep my_string my_file
if [ $? -eq 1 ]
then
echo "Do something"
fi
~Parag



On Wed, Mar 2, 2011 at 9:55 AM, Matt <lm7812 [at] gmail.com> wrote:

> I am looking for a simple way to test if a file does not contain a
> string. This is on a linux box.
>
> if myfile does not contain mystring {
> #do_something;
> }
>
> The file is basically a list of names and I want to test that a
> certain name is not in there. Is there an easy way to do that?
>
> --
> To unsubscribe, e-mail: beginners-unsubscribe [at] perl.org
> For additional commands, e-mail: beginners-help [at] perl.org
> http://learn.perl.org/
>
>
>

--001485f0a01e6b4d89049d83d75d--

--000325555afe9ce855049d83dd44
Content-Type: text/plain; charset=UTF-8

On Wed, Mar 2, 2011 at 10:11 AM, Parag Kalra <paragkalra [at] gmail.com> wrote:

Sorry for the top post. I should have done bottom post. :(

# Untested
> use strict;
> use warnings;
>
> open my $fh, '<', my_file;
> while(<$fh>){
> if ($_ !~ /my_string/) {
> # Do something
> }
> }
>
> The other way would be on shell -
>
> # Untested
> grep my_string my_file
> if [ $? -eq 1 ]
> then
> echo "Do something"
> fi
> ~Parag
>
>


>
> On Wed, Mar 2, 2011 at 9:55 AM, Matt <lm7812 [at] gmail.com> wrote:
>
>> I am looking for a simple way to test if a file does not contain a
>> string. This is on a linux box.
>>
>> if myfile does not contain mystring {
>> #do_something;
>> }
>>
>> The file is basically a list of names and I want to test that a
>> certain name is not in there. Is there an easy way to do that?
>>
>> --
>> To unsubscribe, e-mail: beginners-unsubscribe [at] perl.org
>> For additional commands, e-mail: beginners-help [at] perl.org
>> http://learn.perl.org/
>>
>>
>>
>

--000325555afe9ce855049d83dd44--

The easiest way in my opinion is to use the 'grep' function like this:

my $searchstring=3D"whatever";
open CFG, '<', $_file || die("could not open file: $_file!");
my [at] data=3D<CFG>;
close CFG;
if ( grep /$searchstring/i, [at] data ) {
print "$searchstring found\n";
}

If you negate the grep like this:

[at] data =3D grep !/$searchstring/i, [at] data;

.... you can remove the searchstring from your array (file-text).


best regards
Christian


________________________________________
Von: Matt [lm7812 [at] gmail.com]
Gesendet: Mittwoch, 2. März 2011 18:55
Bis: beginners [at] perl.org
Betreff: Testing File Contents

I am looking for a simple way to test if a file does not contain a
string. This is on a linux box.

if myfile does not contain mystring {
#do_something;
}

The file is basically a list of names and I want to test that a
certain name is not in there. Is there an easy way to do that?

--
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For additional commands, e-mail: beginners-help [at] perl.org
http://learn.perl.org/



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> # Untested
> use strict;
> use warnings;
> open my $fh, '<', my_file;
> while(<$fh>){
> =A0=A0 =A0if ($_ !~ /my_string/) {
> =A0=A0 =A0 =A0 =A0# Do something
> =A0=A0 =A0}
> }

This triggers on EVERY line of the file that does not contain the
string. I just want to trigger once if its no where in the file.


> The other way would be on shell -
> # Untested
> grep my_string my_file
> if [ $? -eq 1 ]
> then
> =A0=A0 =A0echo "Do something"
> fi
> ~Parag
>
>
>
> On Wed, Mar 2, 2011 at 9:55 AM, Matt <lm7812 [at] gmail.com> wrote:
>>
>> I am looking for a simple way to test if a file does not contain a
>> string. =A0This is on a linux box.
>>
>> if myfile does not contain mystring {
>> =A0#do_something;
>> =A0}
>>
>> The file is basically a list of names and I want to test that a
>> certain name is not in there. =A0Is there an easy way to do that?

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> The easiest way in my opinion is to use the 'grep' function like this:
>
> my $searchstring=3D"whatever";
> open CFG, '<', $_file || die("could not open file: $_file!");
> my [at] data=3D<CFG>;
> close CFG;
> if ( grep /$searchstring/i, [at] data ) {
> =A0print "$searchstring found\n";
> }
>

This sorta worked. Needed a minor change.

> unless ( grep /$searchstring/i, [at] data ) {
> print "$searchstring not found\n";

Thanks.

> If you negate the grep like this:
>
> [at] data =3D grep !/$searchstring/i, [at] data;
>
> ... you can remove the searchstring from your array (file-text).
>

>
> I am looking for a simple way to test if a file does not contain a
> string. =A0This is on a linux box.
>
> if myfile does not contain mystring {
> =A0#do_something;
> =A0}
>
> The file is basically a list of names and I want to test that a
> certain name is not in there. =A0Is there an easy way to do that?
>
> --

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---1463803012-1285929251-1299095257=:8309
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Content-Transfer-Encoding: QUOTED-PRINTABLE


On Wed, 2 Mar 2011, Matt wrote:

> > The easiest way in my opinion is to use the 'grep' function like this:
> >
> > my $searchstring=3D"whatever";
> > open CFG, '<', $_file || die("could not open file: $_file!");
> > my [at] data=3D<CFG>;
> > close CFG;
> > if ( grep /$searchstring/i, [at] data ) {
> > =C2=A0print "$searchstring found\n";
> > }
> >
>
> This sorta worked. Needed a minor change.
>
> > unless ( grep /$searchstring/i, [at] data ) {
> > print "$searchstring not found\n";
>
> Thanks.
>

My apologies if I'm beating a dead horse here, but I'm new to Perl and
thought of a slightly different approach:


my $searchrx =3D qr/whatever/; # or q/whatever/ if you don't need regexp
[at] ARGV or die qq/you didn't specify a filename\n/;
open FH, q/</, shift [at] ARGV or die qq/file open error: $!/;
$_ =3D join q//, <FH>;
close FH;
if ( ! m/$searchrx/s ) {
=09print qq/pattern not found\n/;
=09# do something
}


I'm not sure which is more "Perlish", but I hear "TMTOWTDI" is supposed to=

be valued, too. I welcome any criticism.

Brian

---1463803012-1285929251-1299095257=:8309
Content-Type: text/plain; charset=us-ascii

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---1463803012-1285929251-1299095257=:8309--

>From: Brian F. Yulga [mailto:byulga [at] langly.dyndns.org]

>On Wed, 2 Mar 2011, Matt wrote:

> > The easiest way in my opinion is to use the 'grep' function like =
this:
> >
> > my $searchstring=3D"whatever";
> > open CFG, '<', $_file || die("could not open file: $_file!"); my
> > [at] data=3D<CFG>; close CFG; if ( grep /$searchstring/i, [at] data ) {
> > print "$searchstring found\n";
> > }
> >
>
> This sorta worked. Needed a minor change.
>
> > unless ( grep /$searchstring/i, [at] data ) { print "$searchstring not
> > found\n";
>
> Thanks.
>
>
>My apologies if I'm beating a dead horse here, but I'm new to Perl and =
thought of a slightly different approach:
>
>
>my $searchrx =3D qr/whatever/; # or q/whatever/ if you don't need =
regexp

This is probably personal preference, but I prefer to provide a more
meaningful name rather than using [at] ARGV. Plus you have lost the filename
once you 'shifted' [at] ARGV in the open statement. May want to use the file =
name
in the open error statement or later.
Also, I would not use the '/' as your quote delimiter - that's too =
recognizable as
being used as the pattern match delimiter. Use actual double quotes (") =
unless there are
double quotes in the string - also less typing. Instead of '/' may want =
to use '{' and '}'
if using qq (see perldoc perlop, Quote and Quote-like Operators).

my $fileName =3D shift [at] ARGV or die "You did not specify a filename\n";
> [at] ARGV or die qq/you didn't specify a filename\n/;

Use lexical variable for filehandle. Makes things easier - such as =
passing to a function.

open my $FH,'<', $fileName or die "Error opening $fileName: $!\n";
>open FH, q/</, shift [at] ARGV or die qq/file open error: $!/;

The join is unnecessary, set the input_record_separator ($/) to undef or =
use a local
copy of $/ (see perldoc perlvar). If this is undefined, the entire file =
will be read into
a variable.

>$_ =3D join q//, <FH>;
>close FH;
>if ( ! m/$searchrx/s ) {
> print qq/pattern not found\n/;
> # do something
>}
>
>
>I'm not sure which is more "Perlish", but I hear "TMTOWTDI" is supposed =
to
>be valued, too. I welcome any criticism.
>
>Brian

HTH, Ken





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>>>>> "BFY" == Brian F Yulga <byulga [at] langly.dyndns.org> writes:

BFY> My apologies if I'm beating a dead horse here, but I'm new to Perl and
BFY> thought of a slightly different approach:


BFY> my $searchrx = qr/whatever/; # or q/whatever/ if you don't need regexp
BFY> [at] ARGV or die qq/you didn't specify a filename\n/;
BFY> open FH, q/</, shift [at] ARGV or die qq/file open error: $!/;
BFY> $_ = join q//, <FH>;

that is very slow and clunky. perl could slurp the file for you if you
set $/ to undef. or better yet, use File::Slurp to do it

BFY> close FH;
BFY> if ( ! m/$searchrx/s ) {

why are you using m//? the m isn't needed if you use // for delimiters

the OP wants to know if a file has something or not, not to print each
line.

uri

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>>>>> "M" == Matt <lm7812 [at] gmail.com> writes:

M> I am looking for a simple way to test if a file does not contain a
M> string. This is on a linux box.

M> if myfile does not contain mystring {
M> #do_something;
M> }

M> The file is basically a list of names and I want to test that a
M> certain name is not in there. Is there an easy way to do that?

2 lines will do it:

use File::Slurp ;

unless( read_file( $file ) =~ /$whatever/ ) {

# do something
}

faster and cleaner than the line by line methods others have posted.

and if you want even more speed, and the file is long, then shell out to
the grep utility and it has an option to only show you if a line
is/isn't in file. i normally don't recommend shelling out but that would
likely be the fastest solution for a large file.

uri

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--90e6ba25eb2b1ef1d6049d865bfe
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On Wed, Mar 2, 2011 at 3:37 PM, Uri Guttman <uri [at] stemsystems.com> wrote:

> >>>>> "M" == Matt <lm7812 [at] gmail.com> writes:
>
> 2 lines will do it:
>
> use File::Slurp ;
>
> unless( read_file( $file ) =~ /$whatever/ ) {
>
> # do something
> }
>
>
> what's better about File::Slurp than just doing:

my( $file, $string ) = [at] argv;
open my $fh, '<', $file;

while( <$fh> ) {
print "found" if /$string/ ;
}

???

--90e6ba25eb2b1ef1d6049d865bfe--

>>>>> "sw" == shawn wilson <ag4ve.us [at] gmail.com> writes:

sw> On Wed, Mar 2, 2011 at 3:37 PM, Uri Guttman <uri [at] stemsystems.com> wrote:
>> >>>>> "M" == Matt <lm7812 [at] gmail.com> writes:
>>
>> 2 lines will do it:
>>
>> use File::Slurp ;
>>
>> unless( read_file( $file ) =~ /$whatever/ ) {
>>
>> # do something
>> }
>>
>>
>> what's better about File::Slurp than just doing:

sw> my( $file, $string ) = [at] argv;
sw> open my $fh, '<', $file;

sw> while( <$fh> ) {
sw> print "found" if /$string/ ;
sw> }

less code, much much faster. you loop over each line. my code does one
regex call and stays inside perl for that. inside perl is usually faster
than running perl op. use the benchmark module and look at the
difference. it will be noticeable.

also your code looks at every line whereas my will match the first time
and then quit. that is another optimization. you could do the same if
you exited the loop upon a match.

uri

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--001485f6c8a04b8caa049d87ac30
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On Mar 2, 2011 4:47 PM, "Uri Guttman" <uri [at] stemsystems.com> wrote:
>
> >>>>> "sw" == shawn wilson <ag4ve.us [at] gmail.com> writes:
>
> sw> On Wed, Mar 2, 2011 at 3:37 PM, Uri Guttman <uri [at] stemsystems.com>
wrote:
> >> >>>>> "M" == Matt <lm7812 [at] gmail.com> writes:
> >>
> >> 2 lines will do it:
> >>
> >> use File::Slurp ;
> >>
> >> unless( read_file( $file ) =~ /$whatever/ ) {
> >>
> >> # do something
> >> }
> >>
> >>
> >> what's better about File::Slurp than just doing:
>
> sw> my( $file, $string ) = [at] argv;
> sw> open my $fh, '<', $file;
>
> sw> while( <$fh> ) {
> sw> print "found" if /$string/ ;
> sw> }
>
> less code, much much faster. you loop over each line. my code does one
> regex call and stays inside perl for that. inside perl is usually faster
> than running perl op. use the benchmark module and look at the
> difference. it will be noticeable.
>

How can I tell or do I figure out if code 'stays inside perl' or not? And,
I'm not exactly sure what you mean by that either?

--001485f6c8a04b8caa049d87ac30--

>-----Original Message-----
>From: Matt [mailto:lm7812 [at] gmail.com]
>Sent: Wednesday, March 02, 2011 11:25
>To: beginners [at] perl.org
>Subject: Re: Testing File Contents
>
>> # Untested
>> use strict;
>> use warnings;
>> open my $fh, '<', my_file;
>> while(<$fh>){
>> =A0=A0 =A0if ($_ !~ /my_string/) {
>> =A0=A0 =A0 =A0 =A0# Do something
>> =A0=A0 =A0}
>> }
>
>This triggers on EVERY line of the file that does not contain the
>string. I just want to trigger once if its no where in the file.

Add a simple switch which is set to zero. Then look for the value you =
want. When found then you should be able to set to nonzero and leave the =
while.
Then you should be able to check: if switch is not true, then send the =
email...

=A0=A0=A0=A0=A0=A0=A0=A0 If you have any questions and/or problems, =
please let me know.
=A0=A0=A0=A0=A0=A0=A0=A0=A0Thanks.
=A0
Wags ;)
David R. Wagner
Senior Programmer Analyst
FedEx Services
1.719.484.2097 Tel
1.719.484.2419 Fax
1.408.623.5963 Cell
http://Fedex.com/us



>
>
>> The other way would be on shell -
>> # Untested
>> grep my_string my_file
>> if [ $? -eq 1 ]
>> then
>> =A0=A0 =A0echo "Do something"
>> fi
>> ~Parag
>>
>>
>>
>> On Wed, Mar 2, 2011 at 9:55 AM, Matt <lm7812 [at] gmail.com> wrote:
>>>
>>> I am looking for a simple way to test if a file does not contain a
>>> string. =A0This is on a linux box.
>>>
>>> if myfile does not contain mystring {
>>> =A0#do_something;
>>> =A0}
>>>
>>> The file is basically a list of names and I want to test that a
>>> certain name is not in there. =A0Is there an easy way to do that?
>
>--
>To unsubscribe, e-mail: beginners-unsubscribe [at] perl.org
>For additional commands, e-mail: beginners-help [at] perl.org
>http://learn.perl.org/
>


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>>>>> "sw" == shawn wilson <ag4ve.us [at] gmail.com> writes:

>> less code, much much faster. you loop over each line. my code does one
>> regex call and stays inside perl for that. inside perl is usually faster
>> than running perl op. use the benchmark module and look at the
>> difference. it will be noticeable.

sw> How can I tell or do I figure out if code 'stays inside perl' or not? And,
sw> I'm not exactly sure what you mean by that either?

a regex will go inside perl's internals and run there. a perl loop as
you wrote will execute perl operations. the perl interpreter is slow
when executing operations (all perl ops, loop, syntax, etc). but once
you get inside an operation it runs fast because the code is in c.

uri

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On 02/03/2011 17:55, Matt wrote:
>
> I am looking for a simple way to test if a file does not contain a
> string. This is on a linux box.
>
> if myfile does not contain mystring {
> #do_something;
> }
>
> The file is basically a list of names and I want to test that a
> certain name is not in there. Is there an easy way to do that?

Hey Matt

If your file is small then this subroutine will do what you need.

sub file_contains {
my $file, $string = [at] _;
open $file, '<', $file or die $!;
my %names = map { chomp; ($_ => 1) } <DATA>;
return $names{$string};
}


HTH,

Rob

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>>>>> "RD" == Rob Dixon <rob.dixon [at] gmx.com> writes:

RD> On 02/03/2011 17:55, Matt wrote:
>>
>> I am looking for a simple way to test if a file does not contain a
>> string. This is on a linux box.
>>
>> if myfile does not contain mystring {
>> #do_something;
>> }
>>
>> The file is basically a list of names and I want to test that a
>> certain name is not in there. Is there an easy way to do that?

RD> Hey Matt

RD> If your file is small then this subroutine will do what you need.

RD> sub file_contains {
RD> my $file, $string = [at] _;

you forgot the () around the my vars.
that will assign the count of [at] _ to $file. not what you want.

perl -le ' [at] foo = qw( a b ) ;my $x, $y = [at] foo ; print "$x $y"'
2


RD> open $file, '<', $file or die $!;
RD> my %names = map { chomp; ($_ => 1) } <DATA>;

don't you mean <$file> there?

RD> return $names{$string};
RD> }

uri

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On 02/03/2011 23:56, Uri Guttman wrote:
>>>>>> "RD" == Rob Dixon<rob.dixon [at] gmx.com> writes:
>
> RD> On 02/03/2011 17:55, Matt wrote:
> >>
> >> I am looking for a simple way to test if a file does not contain a
> >> string. This is on a linux box.
> >>
> >> if myfile does not contain mystring {
> >> #do_something;
> >> }
> >>
> >> The file is basically a list of names and I want to test that a
> >> certain name is not in there. Is there an easy way to do that?
>
> RD> Hey Matt
>
> RD> If your file is small then this subroutine will do what you need.
>
> RD> sub file_contains {
> RD> my $file, $string = [at] _;
>
> you forgot the () around the my vars.
> that will assign the count of [at] _ to $file. not what you want.
>
> perl -le ' [at] foo = qw( a b ) ;my $x, $y = [at] foo ; print "$x $y"'
> 2
>
>
> RD> open $file, '<', $file or die $!;
> RD> my %names = map { chomp; ($_ => 1) }<DATA>;
>
> don't you mean<$file> there?
>
> RD> return $names{$string};
> RD> }

Thanks Uri. It's midnight and I should be in bed :-/

Version 2:

sub file_contains {
my ($file, $string) = [at] _;
open my $fh, '<', $file or die $!;
my %names = map { chomp; ($_ => 1) } <$fh>;
return $names{$string};
}

Rob

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>>>>> "RD" == Rob Dixon <rob.dixon [at] gmx.com> writes:

RD> Thanks Uri. It's midnight and I should be in bed :-/

we should all be in bed!

RD> Version 2:

RD> sub file_contains {
RD> my ($file, $string) = [at] _;
RD> open my $fh, '<', $file or die $!;
RD> my %names = map { chomp; ($_ => 1) } <$fh>;
RD> return $names{$string};
RD> }

did you see my fast slurp version in this thread?

uri

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Ken Slater wrote:
> > From: Brian F. Yulga [mailto:byulga [at] langly.dyndns.org]
>
> > On Wed, 2 Mar 2011, Matt wrote:
>
> >> The easiest way in my opinion is to use the 'grep' function like
> >> this:
> >>
> >> my $searchstring="whatever"; open CFG, '<', $_file || die("could
> >> not open file: $_file!"); my [at] data=<CFG>; close CFG; if ( grep
> >> /$searchstring/i, [at] data ) { print "$searchstring found\n"; }
> >>
> >
> > This sorta worked. Needed a minor change.
> >
> >> unless ( grep /$searchstring/i, [at] data ) { print "$searchstring
> >> not found\n";
> >
> > Thanks.
> >
> >
> > My apologies if I'm beating a dead horse here, but I'm new to Perl
> > and thought of a slightly different approach:
> >
> >
> > my $searchrx = qr/whatever/; # or q/whatever/ if you don't need
> > regexp
>
> This is probably personal preference, but I prefer to provide a more
> meaningful name rather than using [at] ARGV. Plus you have lost the
> filename once you 'shifted' [at] ARGV in the open statement. May want to
> use the file name in the open error statement or later.

I agree with you, saving the filename to a variable is probably a better
practice, in general. In this context it wasn't specified that it was
needed later, so I opted to just 'shift' it to use once.

> Also, I would not use the '/' as your quote delimiter - that's too
> recognizable as being used as the pattern match delimiter. Use actual
> double quotes (") unless there are double quotes in the string - also
> less typing. Instead of '/' may want to use '{' and '}' if using qq
> (see perldoc perlop, Quote and Quote-like Operators).

Good point. I started using generic quotes almost exclusively when I
discovered that they avoided some of the possible shell-interpolation
issues that arise when executing perl "one-liners". I've probably taken
it too far. I can see that '/' is not a great idea. Besides '{' and
'}' as quote delimiters, do you think it's generally tolerated to use
'(', ')', '[', ']' ?

>
> my $fileName = shift [at] ARGV or die "You did not specify a
> filename\n";
> > [at] ARGV or die qq/you didn't specify a filename\n/;
>
> Use lexical variable for filehandle. Makes things easier - such as
> passing to a function.
>
> open my $FH,'<', $fileName or die "Error opening $fileName: $!\n";
> > open FH, q/</, shift [at] ARGV or die qq/file open error: $!/;

Okay, I'll work on breaking that habit. My first "lessons" in Perl used
the "open FH" convention, and I just got used to it.

> The join is unnecessary, set the input_record_separator ($/) to undef
> or use a local copy of $/ (see perldoc perlvar). If this is
> undefined, the entire file will be read into a variable.
>

Oh, I totally forgot about the input_record_separator ( $/ )...
That's WAY better (actually when I wrote the 'join', I was thinking that
I shouldn't need to do it that way!)

Thanks much for the suggestions,

Brian


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Uri Guttman wrote:
> >>>>> "BFY" == Brian F Yulga <byulga [at] langly.dyndns.org> writes:
>
> BFY> My apologies if I'm beating a dead horse here, but I'm new to
> Perl and BFY> thought of a slightly different approach:
>
>
> BFY> my $searchrx = qr/whatever/; # or q/whatever/ if you don't need
> regexp BFY> [at] ARGV or die qq/you didn't specify a filename\n/; BFY>
> open FH, q/</, shift [at] ARGV or die qq/file open error: $!/; BFY> $_ =
> join q//, <FH>;
>
> that is very slow and clunky. perl could slurp the file for you if
> you set $/ to undef. or better yet, use File::Slurp to do it

Yes, definitely better to set $/ to undef.

I'm still trying to get a handle on the libraries at my disposal --
There's so much in CPAN it's hard to know where to start. Is it
equivalently efficient to use IO::All or IO::Simple, or is File::Slurp
truly the best for this purpose?

I ask because I played with IO:All to read files, enjoyed the simple,
intuitive syntax " my $filecontents < io('filename'); ", but (perhaps
naively) assumed the native "open my $fh" to be faster since it doesn't
require a "use" to load a library.

>
> BFY> close FH; BFY> if ( ! m/$searchrx/s ) {
>
> why are you using m//? the m isn't needed if you use // for
> delimiters

Yeah, I know, I don't need it... being verbose (sometimes) keeps a
newbie like me from making silly mistakes :-)

My initial experimentation with Perl has been mostly in a line-by-line
mind-set because I have a tendency to write scripts that are used like:
some-unix-command | perl -wne 'do some processing' > myresults.txt

I'm trying to expand my horizons, thanks for help,

Brian


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On Mar 2, 9:55=A0am, lm7... [at] gmail.com (Matt) wrote:
> I am looking for a simple way to test if a file does not contain a
> string. =A0This is on a linux box.
>
> if myfile does not contain mystring {
> =A0 #do_something;
> =A0 }
>
> The file is basically a list of names and I want to test that a
> certain name is not in there. =A0Is there an easy way to do that?

Yet another way:

perl -0777 -nlE ' say /mystring/ ? "yes" : "no" ' file

See: perldoc perlrun for explanation of -0777

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Charles DeRykus


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On 2011-03-02 19:22, Christian Marquardt wrote:

> open CFG, '<', $_file || die("could not open file: $_file!");

That only dies if $_file is false.
Funny that you did use parentheses with die.

Some '$' characters were missing too:

open my $CFG, '<', $_file
or die "Error opening '$_file', $!";

--
Ruud

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