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in reply to Perl Log file extraction help required

G'day renjoooz,

Welcome to the monastery.

The special variable $` is not a good choice. I recommend you avoid using it whenever possible. Here's an extract of what perlvar has to say about it:

"The use of this variable anywhere in a program imposes a considerable performance penalty on all regular expression matches. ..."

Here's a script (pm_brace_extract.pl) that gives the required output with the input you provided. 

#!/usr/bin/env perl

use 5.010;
use strict;
use warnings;

while (<DATA>) {
    my @caught = /\{([^}]+)/g;
    next unless @caught;
    say for @caught;
}

__DATA__
...................
...................
<CMD> windowSelect 444.235666.5542.2656565.1255
<CMD> spaceObject -fixSide bottom -space 0
Spacing instances ...
Adding vertical channel spacing of 0.0000um between the following
   selected instances/modules:
    {dupe_core/pads/tran_w_1}
    {dupe_core/pads/tran_w_1}
    {dupe_core/pads/htran_d_13}
    {dupe_core/pads/rec_p_14}
    {dup/pads/VDD_ight1}  {dup/pa/GND_g}   
        {dummy_core/pads/dummy_dig22}
    {dupe_core/pads/dummy_dig23}
    {dupe_core/pads/comp_pad1}
    {dupe_core/pad/CORE_vdd1}
<CMD> deselectAll
<CMD> selectInst dummy_core/pads/IO_gnd_right18
<CMD> selectInst dummy_core/pads/IO_vdd_right18
<CMD> uiSetTool move5
..............
...............
....................

[download]

Output:

$ pm_brace_extract.pl
dupe_core/pads/tran_w_1
dupe_core/pads/tran_w_1
dupe_core/pads/htran_d_13
dupe_core/pads/rec_p_14
dup/pads/VDD_ight1
dup/pa/GND_g
dummy_core/pads/dummy_dig22
dupe_core/pads/dummy_dig23
dupe_core/pads/comp_pad1
dupe_core/pad/CORE_vdd1

[download]

-- Ken

Replies are listed 'Best First'.
Re^2: Perl Log file extraction help required
by renjoooz (Initiate) on Sep 22, 2012 at 07:20 UTC

    Thank you for your help.... I just started learning Perl Scripting... So can u please explain these 3 lines of script... 

    my @caught = /\{([^}]+)/g;
next unless @caught;
say for @caught;

    [download]

    Updatei tried that script in this way.......................................... 

    
#!/usr/bin/perl
$fn = "/home/t8.g";
open FP, "$fn" or die "Error in write:$!";
while (<FP>) {
    my @caught = /\{([^}]+)/g;
    next unless @caught;
    say for @caught;
    print @caught, "\n";
}

    [download]
    but i got result as............................................... 
    dummy_core/pads/hdmi_tx_1
dummy_core/pads/hdmi_tx_2
dummy_core/pads/hdmi_tx_3
dummycore/pads/hdmi_tx_4
dummy_core/pads/IO_vdd_right25
dummy_core/pads/IO_gnd_right2dummy_core/pads/dummy_dig22
dummy_core/pads/dummy_dig23
dummy_core/pads/comp_pad1
dummy_core/pad/CORE_vdd1

    [download]

    I am getting that 2 occurrence line in a single line.... Can you please update it.....

[reply]
[d/l]
[select]

      I certainly don't mind explaining but perhaps you could be a bit more specific regarding what's causing you problems.

      The regexp looks for an opening brace (\{) followed by 1 or more characters that are not a closing brace ([^}]). See perlre.

      If no matches were found, the next line of input is read. See next and unless.

      Loop through what was captured and output. See say and for.

      All the documentation links I've provided here are to pages on http://perldoc.perl.org/. I have that link bookmarked and use it often: I suggest you do the same.

      It's good that you're wrapping your code and data in <code>...</code> tags. It's less good that you're wrapping everything in these tags. If it's not code or data, paragraph tags (<p>...</p>) are usually more appropriate. Take a look at Writeup Formatting Tips.

      -- Ken

[reply]
[d/l]
[select]

      If you are not useing perl 5.010 'use 5.010' then mabe this will work.

      #!/usr/bin/env perl

#use 5.010;
use strict;
use warnings;

while (<DATA>) {
    my @caught = /\{([^}]+)/g;
    next unless @caught;
    #say for @caught;
    foreach (@caught){print $_."\n"};
}

__DATA__
...................
...................
<CMD> windowSelect 444.235666.5542.2656565.1255
<CMD> spaceObject -fixSide bottom -space 0
Spacing instances ...
Adding vertical channel spacing of 0.0000um between the following
   selected instances/modules:
    {dupe_core/pads/tran_w_1}
    {dupe_core/pads/tran_w_1}
    {dupe_core/pads/htran_d_13}
    {dupe_core/pads/rec_p_14}
    {dup/pads/VDD_ight1}  {dup/pa/GND_g}   
        {dummy_core/pads/dummy_dig22}
    {dupe_core/pads/dummy_dig23}
    {dupe_core/pads/comp_pad1}
    {dupe_core/pad/CORE_vdd1}
<CMD> deselectAll
<CMD> selectInst dummy_core/pads/IO_gnd_right18
<CMD> selectInst dummy_core/pads/IO_vdd_right18
<CMD> uiSetTool move5
..............
...............
....................

      [download]
[reply]
[d/l]

        G'day Generoso,

        You can add -l to the shebang line instead of restructuring the code. This produces the same output: 

        #!/usr/bin/env perl -l

use strict;
use warnings;

while (<DATA>) {
    my @caught = /\{([^}]+)/g;
    next unless @caught;
    print for @caught;
}

        [download]

        See perlrun for a description of this option.

        -- Ken

[reply]
[d/l]
[select]
        </code> THIS TIME ITS PERFECT THANKS A LOT </code>
[reply]

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