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I have come across a problem with incompatibility between character and byte semantics. Specifically my program is mixing XML config files via XML::Simple and remote SSH connections via Net::SSH::Perl. I am using perl 5.6.0 on Linux RH7.1.

Basically the problem manifested itself when I tried to use my XML derived configuration data (host, loginid) with the ssh connections supported in Net::SSH::Perl. Apparently Perl was treating my strings with character semantics and this causes strange and inconsistent problems when sending the data to the SSH module. I understand this is due to how SSH does its serialization.

Generally the result was complete failure to authenticate to the server, sometimes it did authenticate, but inconsistently.

My solution was to place the following at the beginning of my script.

use Net::SSH::Perl;
use XML::Simple;
use bytes;

The use bytes pragma disables character semantics within its lexical scope (at least according to the man page).

I may be able to move the use bytes; around to a tighter scope as my script gets more complex.

My questions are, is this the best way to deal with Character v Byte semantics in this situation? Are there any "negative" effects that I should expect by doing this? and if so what can I do to minimize any negative effects?

Thanks for any input.


In reply to What is the proper way to deal with Char v. Byte Semantics by mongre345

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