Hi - first post here :-) I want to read a file thats changing and print the line within that file thats changing - the file isnt being appended to but the lines within the file are changing (hope thats clear!)

I wrote a perl script - works which is good, however as I'm learning perl I'm sure theres a better way of doing this - essentially I'm using a loop, opening file, reading line, extracting data from line, closing file, then sleeping 10 secs then repeating.. instead of doing numerous open/close what would people suggest - I've thought maybe opening, reading then seeking back to start - however that didnt seem to pick updates..

ideas welcome!numpty code follows:- 

#!/usr/bin/perl -w
# program to print out cumulative interrupt for network device drivers
use strict;
#use diagnostics;

while (1) {
open(PFS,"/proc/interrupts")||die "Cant open file $! \n";

while (<PFS>) {
  if ( $_ =~ "eth" ) {
# change print format here .. overlay and have headers
  print $_;
  }
#  seek(PFS,0,1);
#  print tell PFS;
}

close(PFS);
sleep(10);
}

[download]
Thanks Slogger.

In reply to reading a changing file by slogger

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