Any time you encounter mystery characters in your data, you should do a hex dump so that you know exactly what those characters are (guessing can work, but can bite you later if you guess wrong). If you haven't done so, try replacing this: 
@test = split (//,$something);
foreach (@test) {print "$_\n";}

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with: 
for (split //, $something) {
  printf "%02X ", ord;
}

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Given the input "J\x00O\x00H\x00N\x00" this will print: 
4A 00 4F 00 48 00 4E 00

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With that said, as far as I can tell, if your string contains embedded NULLs, your browser should interpret them as whitespace, so that it appears that there is a single space where each NULL character would be expected to appear. This would render your example as: J O H N

If you're not seeing this behavior when interfacing with the CGI, but you are seeing it in the shell, you should probably do some testing to find out if the mystery characters show up in both environments. If not, then there's a problem with the environment in which your script is running (when running from the shell).

In reply to Re: DBI returns NULL characters in string by converter
in thread DBI returns NULL characters in string by jcbyrne

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