Memory maps

[Fu-hau Hsu]

Dear freinds:

 I have following questions about memory maps. I appreciate any
suggestion.

 Q. (1)When a process is running, how can I get the range of data, stack,
       and code segments, say the stack segment is from address 0x..... to
       0x..... so do data segments and code segments?
       PS: Under ELF format, there are several seperaed code and data
           segments, but the process control table has only one pair of
           pointers for each, Are the pointers still useful?
    
    (2) /proc/*/maps will show us those info, but how does it get these
       info? 

FuHau