in reply to Search for a string in a file and get the string in the next line

TMTOWTDI. This example has embedded data, to read from a file then replace DATA with a file handle, see open to open a file and obtain the filehandle:
use warnings;
use strict;

while(<DATA>) {

    if (/PSP-Ri/) {
        $_ = <DATA>;

        # Grab the text after '--'
        my $pairs = (split('--'))[1];

        # Remove that pesky (0x1)
        $pairs =~ s/\(.*?\)//;

        # Create a hash from (key<spaces>value)
        my %hash = split(/\s+/,$pairs);

        # Print the hash
        while (my($k,$v) = each(%hash)) {
            print "$k = $v\n"
        }
    }
}

__DATA__
125 09082010 093627.953624:1.01.00.27144.Info .CC: *GCID:0x00000013--I
+ngress PSP-Ri 
206 09082010 093627.953812:1.01.00.27145.Info .CC: *GCID:0x00000013--C
+odec G711 (0x1) pktSize 20 attrib 0x1c00

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Re^2: Search for a string in a file and get the string in the next line
by moritz (Cardinal) on Oct 11, 2010 at 12:16 UTC
    There are two problems with reading from the file handle inside the while loop:
    1. To get robust code, you have to check if you're at the end of the file while reading from the file
    2. If you have two matching lines in a row, and both the second and the following line to be printed, you have to take special precautions

    Which is why I generally prefer the approach of using a flag 

    use strict;
use warnings;
my $flag = 0;
while (<DATA>) {
    if ($flag) {
         # print parts of $_ as necessary
    }
    $flag = /Ingress PSP/;
}

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