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perl - file reading - last line not displayed

 
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# 1  
Old 12-15-2006
perl - file reading - last line not displayed
Hi,

Here is something that am trying with perl
Code:
#! /opt/third-party/bin/perl

open(fh, "s") || die "unable to open the file <small>";

@ch = ();
$i = 0;

while( $content = <fh> )
{
  if( $i <= 5 ) {
    push(@ch, $content);
    $i++;
  }
  else {
    $i = 1;
    foreach(@ch) {
      print "The file content is $_";
    }
    @ch = ();
  }
}

foreach(@ch) {
  print "The file content is $_";
}

exit 0

The last line is not displayed in any case, could you please provide some pointers for that?

Thanks Smilie
# 2  
Old 12-15-2006
Would you provide a test file and the expected output?
# 3  
Old 12-15-2006
Thanks!

Here is what you have asked for

Code:
>cat s

abcd
adding
more
and then
wow is that working
abcd
last line

Code:
>>perl script.pl

The file content is abcd
The file content is adding
The file content is more
The file content is and then
The file content is wow is that working
The file content is abcd

You could apparently see that the last line from the file 's' is missing
# 4  
Old 12-15-2006
Code:
if( $i <= 6 )

# 5  
Old 12-16-2006
Do you mean this?

Code:
while( $content = <fh> )
{
  if( $i <= 5 ) {
    push(@ch, $content);
    $i++;
  }
  else {
    $i = 1;
    foreach(@ch) {
      print "The file content is $_";
    }
    @ch = ($content);
  }
}

What would you like to do actually with your program, as I don't really understand? It seems like you may wish to buffer 5 or 6 lines of a file before output, but why do that?
# 6  
Old 12-18-2006
Quote:
Originally Posted by anbu23
Code:
if( $i <= 6 )


I dont think this is the right way to do by altering the index counter value as the value suggested will not work for files of different sizes and different lines
# 7  
Old 12-18-2006
Quote:
Originally Posted by cbkihong
Do you mean this?

Code:
while( $content = <fh> )
{
  if( $i <= 5 ) {
    push(@ch, $content);
    $i++;
  }
  else {
    $i = 1;
    foreach(@ch) {
      print "The file content is $_";
    }
    @ch = ($content);
  }
}

What would you like to do actually with your program, as I don't really understand? It seems like you may wish to buffer 5 or 6 lines of a file before output, but why do that?
Thanks for the reply.

What am trying to do is, buffer some 'n' lines, do some processing ( probably here its display) and then continue till the end.
Code:
$ch = ();

#am trying to empty the array and fill it afresh with the new set of contents from the file.

Could you please explain whats happening with.
Code:
$ch = ($content);

 
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