Tried to improve it by adding headers:

#!/bin/sh
PATHFILE=$1
SHORTFILE=`basename "$PATHFILE"`

perl -i.orig -ple  'BEGIN{$/=undef} $_= "begin 600 $ENV{SHORTFILE}\n".
+(pack 'u', $_)."`\nend" if $_' $1
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It can be enhanced by checking the file permissions and setting those too, instead of the hardcoded 600