in reply to Parse the text file output and delete files

Just parse your file once and only forward.

Keep track in a variable at all time of the last executing: @ ... dir1.sql encountered, and, when you meet an ERROR line, you know that you can delete the SQL file whose name is in the last-sql-file variable (if the file still exists).

No need to read backward.

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Re^2: Parse the text file output and delete files
by Gaurav99 (Initiate) on Jul 20, 2015 at 16:59 UTC
    I am very new to perl.Will really appreciate if I have the script for the logic above.
[reply]

      I would explore the tutorials you can find here. Or google "perl basic file operations". Make some effort - you'll learn more that way!

      Dum Spiro Spero
[reply]
      Hi,

      the general basic idea might perhaps be something like this: 

      my $last_sql_file;
while (my $line = <$LOG>) {
    chomp $line;
    $last_sql_file = $1 if $line =~ /^executing: \@(.+)/;
    if ($line =~ /^ERROR at/) {
        unlink $last_sql_file if -f $last_sql_file; # don't try to del
+ete this file if it was already deleted on a previous error
    }
}

      [download]
      That's the basic algorithm, please fell free to ask if you don't understand it. I leave it to you to find out in the documentation how to open the log file if you don't know how (clue: take a look at open).
[reply]
[d/l]

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