On Aug 15, 11:38 am, [EMAIL PROTECTED] (Toddy Prawiraharjo) wrote:
> Is it possible to read only part of file in perl?
Yes. You can stop reading at any time.
> At this moment I have script similar to:
>
> open (FH, "file");
> @FH = <FH>;
Well there's your problem. You just read the entire file, all at
once.
> foreach $line(@FH){
And now you're just looping through an array of strings. There is no
longer a concept of "file".
> processing linebyline}
No. You're not processing line by line. You already read ALL lines
into one giant array.
> close FH;
>
> However, I only need certain part of file only to be read (let say beginning
> 20 lines).
So do that. Only read 20 lines. Don't read the whole file.
open my $fh, '<', "file" or die $!;
while (my $line = <$fh>) {
process_line($line);
last if $. == 20;
}
> Above method will be taking lot of time to read file up to 5mb in
> size (.ps file), so how do I this in perl? Any module or other slick way?
>
> So far my solution is using system call using unix's head -n 20.
Find whoever or whatever told you to process a file by reading all
lines into an array, and smack them around a little. Horrible
programming habbit to get into.
Paul Lalli
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