Hello PerlMonks,

From a device I get binary data, and in this data I need to replace a (binary sub-)string by another one. I thought that I could simply read the data into a string and hoped that s/$cut/$place/g would do the trick. No such luck.

Can it be done using Perl? If so: how? The length of $cut and $place are identical, the location is unknown.

Thanks

update, made a variation on my original testcode to see if I could find the index:

my $datafile=<file with binary data>;
my $searchdata=<file with string to be replaced>;
my ($FH,$buf, $cut);
binmode($FH);
open ($FH, $datafile);
read($FH, $buf, 10000);
chop($buf);
close ($FH);
open ($FH,$searchdata );
read($FH, $cut, 100);
chop($cut);
close($FH);
my $result = index($buf,$cut);
print "position: $result\n";
[download]

Update 2: made new testdata, and the code works! Thanks!

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