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copied!<p>The Perl format <code>"nNcc"</code> is equivalent to the Python format <code>"!HLbb"</code>. There is no direct equivalent in Python for Perl's <code>"H*"</code>.</p> <p>There are two problems.</p> <ul> <li>Python's <code>struct.unpack</code> does not accept the wildcard character, <code>*</code></li> <li>Python's <code>struct.unpack</code> does not "hexlify" data strings</li> </ul> <p>The first problem can be worked-around using a helper function like <code>unpack</code>.</p> <p>The second problem can be solved using <code>binascii.hexlify</code>:</p> <pre class="lang-py prettyprint-override"><code>import struct import binascii def unpack(fmt, data): """ Return struct.unpack(fmt, data) with the optional single * in fmt replaced with the appropriate number, given the length of data. """ # http://stackoverflow.com/a/7867892/190597 try: return struct.unpack(fmt, data) except struct.error: flen = struct.calcsize(fmt.replace('*', '')) alen = len(data) idx = fmt.find('*') before_char = fmt[idx-1] n = (alen-flen)//struct.calcsize(before_char)+1 fmt = ''.join((fmt[:idx-1], str(n), before_char, fmt[idx+1:])) return struct.unpack(fmt, data) data = open('data').read() x = list(unpack("!HLbbs*", data)) # x[-1].encode('hex') works in Python 2, but not in Python 3 x[-1] = binascii.hexlify(x[-1]) print(x) </code></pre> <p>When tested on data produced by this Perl script:</p> <pre><code>$line = pack("nNccH*", 1, 2, 10, 4, '1fba'); print "$line"; </code></pre> <p>The Python script yields</p> <pre><code>[1, 2, 10, 4, '1fba'] </code></pre>

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