If you declare $SousMaintenance within prov.pl, like so:

#!/usr/bin/perl
# prov.pl
use strict;
use warnings;
use vars qw( $SousMaintenance );

require './inc.pl';

print $SousMaintenance,"\n";
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with an inc.pl like:

$SousMaintenance = 'value one';
1;
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the problem goes away. Another idea for you is to include a package declaration within inc.pl so that you create a namespace (seperate from main::) like so:

# inc.pl
package myInc;
$SousMaintenance = 'value one';
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Then call it like this within prov.pl:

print $myInc::SousMaintenance,"\n";
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cp
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