/usr/share/kannel/contrib/webalizer/split.pl is in kannel-extras 1.4.3-2fakesync2build1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 | #!/usr/bin/perl -w
# This script reads access.log (pass it through multi-line first!) and
# split them by SMSC or Service
# Just define your service and smsc names as:
#
# SMSC: (smsc-id in smsc groups)
# <Client>-<Number>
#
# Service: (name in sms-service and sendsms-user)
# <Client>-<SVC>-<service_name>
# SVC = for user, MT or USER
#       for service, MO or SERVICE
$dir = shift || "/tmp";
foreach $line (<>) {
	
	$line =~ /^.{19} (.+) \[SMSC:(.*?)\] \[SVC:(.*?)\].*$/; 
	$status= $1; $smsc= $2; $service= $3;
	if( $status =~ /Receive/) {
		open(X, ">>$dir/$smsc.log");
	} else {
		open(X, ">>$dir/$service.log");
	}
	print X $line;
	close(X);
}
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