Re: how does ld.so call ELF's entry?

[Sofiane Akermoun <akersof@xxxxxxxxx>]

EntryPoint is set in the ELF Header at assembling/linking time.

2013/4/7 ishare <june.tune.sea@xxxxxxxxx>:
> On Sat, Apr 06, 2013 at 08:43:16PM -0700, Chris Evans wrote:
>> With a far jump to entry offset
>
>   How does it know the entry point's address?
>
>>
>>
>> Sent from my iPad
>>
>> On Apr 6, 2013, at 8:39 PM, ishare <june.tune.sea@xxxxxxxxx> wrote:
>>
>> > On Sun, Apr 07, 2013 at 05:11:28AM +0200, Sofiane Akermoun wrote:
>> >> Hello,
>> >>
>> >>
>> >> The interpreter is specified during linking process and the program header
>> >> of your binary is filled with good values.
>> >> Then when the operating system load your binary, he finds next the
>> >> interpreter to use.
>> >> The linker ld sets the good values by default but you can overwrite it or
>> >> specify other values if you want.
>> >> The steps are:
>> >> 1)The operating system loads your binary
>> >> 2)The program loader system execute the Interpreter specifiy in the binary
>> >> 3)The interpreter gather all the dynamic libraries needed in memory
>> >
>> >
>> >> 4)The Control is passed to the entry point of your program
>> >
>> >  How does  the step 4 been  done ?
>> >
>> >  thanks!
>> >>
>> >> The entry point is specified in your code source as a "global". And could
>> >> be find in your object file by the linker.
>> >> In theory there are some default tag to specify entry point, like "..start"
>> >> for nasm, but you can also passed it to the linker.
>> >>
>> >> regards,
>> >>
>> >> Sofiane Akermoun
>> >> akersof@xxxxxxxxx
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> 2013/4/7 ishare <june.tune.sea@xxxxxxxxx>
>> >>
>> >>>
>> >>>  For an ELF ,which needs a interpreter , how is it  been called by the
>> >>> interpreter ?
>> >>>
>> >>>  As I know the interpreter is loaded first and do something essential
>> >>> ,then call the main routine of ELF .
>> >>>  How is this procedure implemented ?
>> >>>
>> >>>  Thanks!
>> >>> --
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>> >>
>> >>
>> >>
>> >> --
>> >> Sofiane AKERMOUN
>> >> akersof@xxxxxxxxx
>> > --
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-- 
Sofiane AKERMOUN
akersof@xxxxxxxxx
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