ctypes_dump.py

import ctypes as c
import string
import logging; log = logging.getLogger(__name__)
# ...

def dump(obj, logger=log.info):                                                 
    # assert isinstance(obj, c.C_TYPE)                                          
    B = []                                                                      
    C = []                                                                      
    offset = 0                                                                  
    last = ''                                                                   
    count = 0                                                                   
    raw = c.cast(c.addressof(obj), c.POINTER(c.c_char * c.sizeof(obj))).contents.raw # THIS IS WHAT YOU'RE LOOKING FOR
    logger('%s size: %u = 0x%x', '*' * 8, len(raw), len(raw))                   
    for x in raw:                                                               
        C.append(x if x in string.printable and not x.isspace() else '.')       
        B.append('%02x' % (ord(x),))                                            
        if len(C) == 16:                                                        
            s = ' '.join(B) + ' ' + ''.join(C)                                  
            if last != s:                                                       
                if count:                                                       
                    logger('%s %s', '*' * 8, count)                             
                    count = 0                                                   
                logger('%08x %s', offset, s)                                    
                last = s                                                        
            else:                                                               
                count += 1                                                      
            offset += 16                                                        
            while C: C.pop()                                                    
            while B: B.pop()                                                    
    if count:                                                                   
        logger('%s %s', '*' * 8, count)                                         
    if C:                                                                       
        while len(C) < 16:                                                      
            C.append(' ')                                                       
            B.append('  ')                                                      
        logger('%08x %s %s', offset, ' '.join(B), ''.join(C))                   

# EOF #

Code like

import ctypes as c
# ...
b10 = c.c_char(10)()
b10.value = '\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a'
dump(b10)

Writes something like

INFO:MyMod:******** size: 10 = 0xa
INFO:MyMod:00000000 01 02 03 04 05 06 07 09 0a                    ..........