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Simple Question about Reading file by Perl

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# 1  
Old 11-10-2011
Simple Question about Reading file by Perl
Hi ,

I just write a simple function to read the file line by line.
But when I run it it says out of memory.
I am not sure about the root cause, Can someone help me out of this?
Smilie

Code:
#! /usr/bin/perl

use strict;

sub checkAPs{
        my $NDPDir = "/home/eweiqqu/NCB/NDP_files/";
        my $gsnFile = $NDPDir . "gsn.cbd";
        print $gsnFile."\n";
        my @aps = ();
        open Handler, $gsnFile or die "cannot open gsn.cbd";
        my @lines =<Handler>;
        while (@lines){
                push @aps, $3;
        }
        close(Handler);
        while (@aps){
                print $_." ";
        }
}

&checkAPs;

# 2  
Old 11-10-2011
Quote:
Originally Posted by Damon_Qu
...
I just write a simple function to read the file line by line.
But when I run it it says out of memory.
I am not sure about the root cause, Can someone help me out of this?

Code:
#! /usr/bin/perl

use strict;

sub checkAPs{
        my $NDPDir = "/home/eweiqqu/NCB/NDP_files/";
        my $gsnFile = $NDPDir . "gsn.cbd";
        print $gsnFile."\n";
        my @aps = ();
        open Handler, $gsnFile or die "cannot open gsn.cbd";
        my @lines =<Handler>;
        while (@lines){
                push @aps, $3;
        }
        close(Handler);
        while (@aps){
                print $_." ";
        }
}

&checkAPs;

You are **NOT** reading the file line by line. You are storing the entire file contents into an array called @lines. So if your file is huge, the program will run out of memory.

tyler_durden
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