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| Gerald Host 2006-10-19, 6:56 pm |
| I'm trying to read a text file line-by-line.
open IN, shift;
my @lines=split("\n",<IN> );
foreach my $line (@lines) {
print OUT "QQQ $line QQQ\n";
}
The problem is that it always gives me the entire file, not line by line.
What did I do wrong? Other things I've tried:
open IN, shift;
while (my $line =<IN> ) {
print OUT "QQQ $line QQQ\n";
}
Ryan
| |
| DJ Stunks 2006-10-19, 6:56 pm |
| Gerald Host wrote:
> I'm trying to read a text file line-by-line.
>
> open IN, shift;
> my @lines=split("\n",<IN> );
> foreach my $line (@lines) {
> print OUT "QQQ $line QQQ\n";
> }
>
> The problem is that it always gives me the entire file, not line by line.
> What did I do wrong? Other things I've tried:
>
> open IN, shift;
> while (my $line =<IN> ) {
> print OUT "QQQ $line QQQ\n";
> }
>
and how did that second try work out for you?
-jp
| |
| Gerald Host 2006-10-19, 6:56 pm |
| I tried both, and they typically do work for me, but right now they just
aren't...
QQQ line1....
line2
line3
....
lineX QQQ
any ideas?
Ryan
On 10/19/06, Helliwell, Kim <Kim.Helliwell@lsi.com> wrote:
>
> Another way:
>
> foreach $line (<IN> )
> {
> ...
> }
>
> if you don't want to slurp all the lines into an array (to save memory).
>
> Kim Helliwell
> LSI Logic Corporation
> Work: 408 433 8475
> Cell: 408 832 5365
> kim.helliwell@lsi.com
>
> Please Note: My email address will change to kim.helliwell@lsi.com on
> Oct 14. The old 'lsil.com' email address will stop working after Jan 15,
> 2007. Please update your address book and distribution lists
> accordingly. Thank you.
>
> -----Original Message-----
> From: Gerald Host [mailto:ghost@madisonip.com]
> Sent: Thursday, October 19, 2006 3:35 PM
> To: Perl List
> Subject: reading a file
>
> I'm trying to read a text file line-by-line.
>
> open IN, shift;
> my @lines=split("\n",<IN> );
> foreach my $line (@lines) {
> print OUT "QQQ $line QQQ\n";
> }
>
> The problem is that it always gives me the entire file, not line by
> line.
> What did I do wrong? Other things I've tried:
>
> open IN, shift;
> while (my $line =<IN> ) {
> print OUT "QQQ $line QQQ\n";
> }
>
>
> Ryan
>
| |
| Jenda Krynicky 2006-10-19, 6:56 pm |
| From: "Gerald Host" <ghost@madisonip.com>
> I'm trying to read a text file line-by-line.
>
> open IN, shift;
> my @lines=split("\n",<IN> );
Did you ever read the docs???
my @lines=<IN>;
The <> operator returns the list of lines in the file if called in
the list context.
> foreach my $line (@lines) {
> print OUT "QQQ $line QQQ\n";
> }
>
> The problem is that it always gives me the entire file, not line by
> line. What did I do wrong? Other things I've tried:
>
> open IN, shift;
> while (my $line =<IN> ) {
> print OUT "QQQ $line QQQ\n";
> }
This one should work.
Are you sure you did not touch $/ beforehand? This is the variable
that specifies what's the line delimiter. If you undefine it you'll
get the whole file as the first and only line.
Jenda
===== Jenda@Krynicky.cz === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery
| |
| usenet@DavidFilmer.com 2006-10-19, 6:56 pm |
| Gerald Host wrote:
> open IN, shift;
Always check and report failure on I/O operations:
open IN, shift or die "Oops - $!\n";
(and use lexical variables for filehandles).
--
The best way to get a good answer is to ask a good question.
David Filmer (http://DavidFilmer.com)
| |
| Xavier Mas 2006-10-19, 9:56 pm |
| A Divendres 20 Octubre 2006 00:34, Gerald Host va escriure:
> I'm trying to read a text file line-by-line.
>
> open IN, shift;
> my @lines=split("\n",<IN> );
> foreach my $line (@lines) {
> print OUT "QQQ $line QQQ\n";
> }
>
> The problem is that it always gives me the entire file, not line by line.
> What did I do wrong? Other things I've tried:
>
> open IN, shift;
> while (my $line =<IN> ) {
> print OUT "QQQ $line QQQ\n";
> }
>
>
> Ryan
Im my @lines you are giving all the file in one shot. read de the file line by
line using a while loop inserting all last chunk of code into it.
--
Xavier Mas
| |
| Kim Helliwell 2006-10-20, 3:58 am |
| Try using:
my @lines =3D <IN>;
I don't think you need the split, and it's goofing things up.
I know the above works, because I use it all the time.
Kim Helliwell
LSI Logic Corporation
Work: 408 433 8475
Cell: 408 832 5365
kim.helliwell@lsi.com
=20
Please Note: My email address will change to kim.helliwell@lsi.com on
Oct 14. The old 'lsil.com' email address will stop working after Jan 15,
2007. Please update your address book and distribution lists
accordingly. Thank you.
-----Original Message-----
From: Gerald Host [mailto:ghost@madisonip.com]=20
Sent: Thursday, October 19, 2006 3:35 PM
To: Perl List
Subject: reading a file
I'm trying to read a text file line-by-line.
open IN, shift;
my @lines=3Dsplit("\n",<IN> );
foreach my $line (@lines) {
print OUT "QQQ $line QQQ\n";
}
The problem is that it always gives me the entire file, not line by
line.
What did I do wrong? Other things I've tried:
open IN, shift;
while (my $line =3D<IN> ) {
print OUT "QQQ $line QQQ\n";
}
Ryan
| |
| Kim Helliwell 2006-10-20, 3:58 am |
| Another way:
foreach $line (<IN> )
{
....
}
if you don't want to slurp all the lines into an array (to save memory).
Kim Helliwell
LSI Logic Corporation
Work: 408 433 8475
Cell: 408 832 5365
kim.helliwell@lsi.com
=20
Please Note: My email address will change to kim.helliwell@lsi.com on
Oct 14. The old 'lsil.com' email address will stop working after Jan 15,
2007. Please update your address book and distribution lists
accordingly. Thank you.
-----Original Message-----
From: Gerald Host [mailto:ghost@madisonip.com]=20
Sent: Thursday, October 19, 2006 3:35 PM
To: Perl List
Subject: reading a file
I'm trying to read a text file line-by-line.
open IN, shift;
my @lines=3Dsplit("\n",<IN> );
foreach my $line (@lines) {
print OUT "QQQ $line QQQ\n";
}
The problem is that it always gives me the entire file, not line by
line.
What did I do wrong? Other things I've tried:
open IN, shift;
while (my $line =3D<IN> ) {
print OUT "QQQ $line QQQ\n";
}
Ryan
| |
| Anshul Saxena 2006-10-20, 6:56 pm |
| Hi add this line before your code
$/ = "\n";
What this does is breaks your file reading sequence at every new line so
that each new line is stored as a separate item in the array you are using.
Lemme know if this helps or doesn't.
On 10/19/06, Gerald Host <ghost@madisonip.com> wrote:
>
> I tried both, and they typically do work for me, but right now they just
> aren't...
>
> QQQ line1....
> line2
> line3
> ...
> lineX QQQ
>
> any ideas?
>
> Ryan
>
> On 10/19/06, Helliwell, Kim <Kim.Helliwell@lsi.com> wrote:
>
>
| |
| Paul Lalli 2006-10-20, 6:56 pm |
| Kim Helliwell wrote:
> Another way:
>
> foreach $line (<IN> )
> {
> ...
> }
>
> if you don't want to slurp all the lines into an array (to save memory).
You are extraordinarily  . This DOES slurp the entire file into
memory. It builds an in-memory list of all the lines of the file, and
only *then* does it proceed to process each element of this list.
The way to avoid slurping the file is to use while rather than foreach:
while (my $line = <IN> ) {
#...
}
Paul Lalli
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