Help needed with translating perl to python

[vj]

I have a perl script which connect to network stream using sockets.
The scripts first logins in to the server and then parses the data
comming from the socket.

Statement 1:
my $today = sprintf("%4s%02s%02s", [localtime()]->[5]+1900,
[localtime()]->[4]+1, [localtime()]->[3]) ;
Statement 2:
my $password = md5_hex("$today$username") ;

Statement group 3:

$msglen = bcdlen(length($msg)) ;

sub bcdlen {
my $strlen = sprintf("%04s", shift) ;
my $firstval = substr($strlen, 2, 1)*16 + substr($strlen, 3, 1) ;
my $lastval = substr($strlen, 0, 1)*16 + substr($strlen, 1, 1) ;
return chr($firstval) . chr($lastval) ;
}

[vj]

I posted too soon:

Statement 1:
my $today = sprintf("%4s%02s%02s", [localtime()]->[5]+1900,
[localtime()]->[4]+1, [localtime()]->[3]) ;

1. is localtime the same as time in python?
2. What does -? do in perl?
3. What is 'my'

Statement 2:
my $password = md5_hex("$today$username") ;

is md5_hex the same as md5.new(key).hexdigest() in python?

$msglen = bcdlen(length($msg)) ;

1. here the funciton is being called with the length of variable msg.
However the function def below does not have any args

sub bcdlen {
my $strlen = sprintf("%04s", shift) ;
my $firstval = substr($strlen, 2, 1)*16 + substr($strlen, 3, 1) ;
my $lastval = substr($strlen, 0, 1)*16 + substr($strlen, 1, 1) ;
return chr($firstval) . chr($lastval) ;

}

2. What does shift do above?
3. is the '.' operator just + in python?

Thanks,

Vineet

[attn.steven.kuo]

On Jun 26, 8:04 am, vj <[e-mail]:

I have a perl script which connect to network stream using sockets.
The scripts first logins in to the server and then parses the data
comming from the socket.

Statement 1:
my $today = sprintf("%4s%02s%02s", [localtime()]->[5]+1900,
[localtime()]->[4]+1, [localtime()]->[3]) ;

Perl has "Do What I Mean" features that allow you to
treat strings and number interchangeably. Python's
time.localtime returns a tuple of integers so you'll
have to use the proper format conversion characters:

import time
today = "%04d%02d%02d" % time.localtime()[0:3]

# No need to add offsets of 1900 and 1 because Python
# does this for you

>
Statement 2:
my $password = md5_hex("$today$username") ;

You should have added that md5_hex is comes from
Digest::MD5, not a core Perl module. Regardless:
import md5
password = md5.new("%s%s" % (today, username)).hexdigest()

# seems to be what you wanted

Statement group 3:

$msglen = bcdlen(length($msg)) ;

sub bcdlen {
my $strlen = sprintf("%04s", shift) ;
my $firstval = substr($strlen, 2, 1)*16 + substr($strlen, 3, 1) ;
my $lastval = substr($strlen, 0, 1)*16 + substr($strlen, 1, 1) ;
return chr($firstval) . chr($lastval) ;

}

You can have a variadic function in Python but the parameters
are passed via a tuple. Because a tuple is immutable, one cannot
"shift" elements out of a tuple. Here I've used the first parameter
via selection by index. Perl's substr is replaced by slice notation;
chr is, well, chr. Concatenation (Perl's '.' operator) is replaced
by string formatting:

>>def bcdlen(*args):

.... strlen = "%04s" % str(args[0])
.... firstval = int(strlen[2:3]) * 16 + int(strlen[3:4])
.... lastval = int(strlen[0:1]) * 16 + int(strlen[1:2])
.... return "%s%s" % (chr(firstval), chr(lastval))
....

>>bcdlen(4546)

'FE'
--
Hope this helps,
Steven