in reply to How to Execute unix commands like "WC, tail, Gunzip, ZIP" against a file which is read from directory

Alternatively, instead of 

system("wc -l $file");

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you could do 
system("cd $dir; wc -l $file");

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which is less efficient, but if instead of wc you have another command, which works in the current directory, this might even be better.

Of course, most efficient is chdir before you loop over the files (as suggested by smls)

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Re^2: How to Execute unix commands like "WC, tail, Gunzip, ZIP" against a file which is read from directory
by rajsai28 (Novice) on Jun 07, 2013 at 03:10 UTC
    Hi Monks,

    Thanks for your valuable suggestion.

    i have used the below code and it works for me

    can we store the value of unix command in some variable because when we execute the unix command it will either return 0 or 1, i want to store the value

    
chdir($dir);
    foreach my $file (@files) {
        if ($file=~ m/orig/) {
        my $lcmd = system("gunzip -c $file|tail -1");
}

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    Output:

    123456|345627899292|000108418|

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    i want to store the value 123456|345627899292|000108418| in variable so that i can use substr to fetch '000108418'

    Thanks a lot for the valuable inputs

    thanks & regards,
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      Hi Monks,

      i got the syntax and please check below

      my $result = `gunzip -c $file|tail -1`;

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      where i can get the unix command result

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[d/l]

        Maybe you want to read about what the "backticks" operator does. Consult perlop about qx or "backticks".

        Also, in your code snippet, the variable $result was given a name that might indicate its use.

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