tools/logger.pl

   1 #!/usr/bin/perl
   2 # logger.pl: masks long meaningless output with pretty lines of dots
   3 #  Details: 1) reads lines from STDIN and echos them on STDOUT,
   4 #           2) print a '.' to STDERR every $N lines.
   5 #           3) print a newline after a sequence of $C dots
   6
   7 use strict;
   8 use warnings;
   9
  10 # make sure all output gets displayed immediately
  11 $| = 1;
  12
  13 # TODO: add -n and -c options w/ zero checks)
  14 # line and column limits
  15 my $N = 10;
  16 my $C = 72;
  17
  18 # current line and column counters
  19 my $n = 0;
  20 my $c = 0;
  21
  22 # read all lines from STDIN
  23 while (<STDIN>)
  24 {
  25         # echo line to output
  26         print STDOUT $_;
  27         # echo line to console if it is important
  28         if (/(Warning|Error)/) {
  29                 print STDERR "\n" if $c;
  30                 print STDERR $_;
  31                 $c = 0;
  32         }
  33         # only display progress every Nth step
  34         next if ++$n % $N;
  35         print STDERR ".";
  36         # wrap at column C to provide fixed-width rows of dots
  37         print STDERR "\n" unless ++$c % $C;
  38 }
  39
  40 print STDERR "\n" if $c;