in reply to Re^4: Error using grep
in thread Error using grep

Ok. A fairly full on version of that looks like this:

#!/usr/bin/perl use strict; use warnings; use Getopt::Long; my %options; Getopt::Long::GetOptions(\%options, 'all', 'keyword:s', 'help'); my @filenames = @ARGV; if (!exists $options{keyword} || !@filenames || exists $options{help}) + { print <<HELP; search [--all] --keyword <match word> <file list> Searches all files in <file list> and prints the lines where <matc +h word> is found. If --all is provided the entire file containing <match w +ord> is printed. HELP exit; } my $found; for my $fileName (@filenames) { open my $inFile, '<', $fileName or die "Unable to open $fileName: +$!\n"; while (defined(my $line = <$inFile>)) { next if $line !~ /\b\Q$options{keyword}\E\b/; if ($options{all}) { print "\nKeyword $options{keyword} found on line $. of $fi +leName\n"; seek $inFile, 0, 0; print <$inFile>; $found = 1; last; } print $line; $found = 1; } close $inFile; } print "Keyword not found in ", join(', ', @filenames), "\n" if !$found +;

There are a few things to note in that code:

  1. The command line is used to give switches and the list of files to process
  2. The module Getopt::Long is used to process command line switches
  3. The script gives help if it doesn't like the command line parameters or help is asked for using the --help switch
  4. Three parameter open is used and the result checked.
  5. Lexical file handles (my $inFile) are used
  6. seek is used to set the input file back to the start so a simple print <$inFile>; can be used to print the entire file
  7. A found flag is used to keep track of wether a match has been found or not.

A typical command line looks like:

search --keyword "Boot Flash" --all file1.txt file2.txt
True laziness is hard work

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Re^6: Error using grep
by justkar4u (Novice) on Mar 29, 2011 at 23:00 UTC
    Hi, I appreciate your help but I tried to execute your code and I got search command not found error! I tried to use switch command instead but still same error. Your code exits after showing HELP. Finally I was able to fix it :)
    #!/usr/bin/perl use strict; use warnings; if ($#ARGV != 1) { print "Error: Usage- script.pl filename keyword(to be searched)\neg:se +arch.pl config_file XYZ\n"; exit; } our $file=$ARGV[0]; our $key=$ARGV[1]; my $count = 0; if (-e "$file") { open (DATA,$file); chomp($key); # Search for the key pattern in the file information. while (defined (my $line = <DATA>)) { if ($line =~ /\b\Q$key\E\b/i) { #next; print "$line\n"; $count++; } } if($count == 0) { print "Keyword not found\n Search Completed\n"; } close (DATA); } else { print "Error: file does'nt exist\n"; exit; }
    NOTE: This can be run as script.pl randomfile randomkey format