As I understood you want the filename to be user=newvalue and the string "user=newvalue" to be written to that file: 
#!/usr/bin/perl
#
#
use strict;
use warnings;

my $teststring = '"user={hhhfj}jshdfjhdfjh\="';
my $own_value  = "newvalue";

if ( $teststring =~ /\"user=.*/ ) {
    $teststring =~ s /\"user=.*/\"user=$own_value\"/;
    my $filename = $teststring;
    print $teststring, "\n";

    $filename =~ s/\"//g;    #you don't want " in an filename
    open my $outfile, ">", $filename;
    print $outfile $teststring;
    close $outfile;
}

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In reply to Re: Replace a string after a word by walto
in thread Replace a string after a word by nithins

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