Redpill me on e_entry

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3MB, 4896x3672px

Leave this Linus shit behind you and join the red sea

>>60895600
ELF is not OS-specific.

>>60895567
It's the program's entry point, where it begins to execute the code once it's loaded into memory.

>>60895638
Is it there just to make the jump offsets in .text correct? And load linker symbols correctly too?

>>60895600
he didn't mention linux
elf is used in lots of places, even the playstation 2 uses it

>2010 + x
>not using l337 constants

>32-bit constant
>0xB16B00B5

>MAC spoofing
>13A7D3ADBEEF

>>60895666
Yes, and that's because the PS2 also runs Linux

>>60895911
It does not.

>>60895658
it's there so you are able to start the program you idiot

>>60895963
Am I correct so far?

# ELF32 header (52 bytes)
7F 45 4C 46 # signature
01 01 01 00 # ELFCLASS32, ELF2LSB, EV_CURRENT (file version), ELFOSABI_NONE
00 00 00 00 00 00 00 00 # padding
02 00 # executable
03 00 # for Intel 80386 (also known as x86, x86-32 and IA-32)
01 00 00 00 # object file version (EV_CURRENT)
08 04 80 00 # entry point (where the whole ELF file is loaded or _start???)
34 00 00 00 # program header offset: right after ELF header, 52 bytes)
00 00 00 00 # section header offset: no section headers
00 00 00 00 # The Intel386 architecture defines no flags; so this is 0.
34 00 # ELF header size (52 bytes)
20 00 # Program header size (32 bytes)
10 00 # Program header section number
00 00 # e_shentsize
00 00 # e_shnum
00 00 # e_shstrndx

# Program header for ELF32 (32 bytes)
10 00 00 00 # Loadable program segment
00 00 00 00 # Offset of that segment
08 04 80 00 # p_vaddr
08 04 80 00 # p_paddr
?? ?? ?? ?? # file size (don't know yet)
?? ?? ?? ?? # memory size (same as file size)
05 00 00 00 # p_flags
00 10 00 00 # p_align = 4096 bytes

>>60896007
Also, I think that what the OS actually loads is specified in the program header table.

p_type says that this segment the OS will have to load
p_off says the FILE offset that specifies the segment start
p_vaddr says the virtual address of that segment
p_paddr says the actual memory address of that segment

Oh, and I get it now, e_entry says where in the loaded segments to start the execution! I think I get it now, so atm the file is wrong, because I haven't written my _start yet and e_entry will point to that + p_vaddr or p_paddr, don't know yet.

So, at the moment e_entry, p_vaddr and p_paddr are all wrong, but I know how to fix them.

>>60896007
the entry point is where execution starts, the OS processes the ELF, load dynamic librarys etc. and once it's done execution jumps to that address.

>>60896213
Thanks, you explained it well, I understand it now.

>>60895926
>>60895911
it can, but it doesn't while playing ps2 games

>>60895567
There's nothing to redpill about, you meming faggot.
It's the entry point to the program, nothing else.

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4KB, 334x24px

>>60895681
>>0xB16B00B5
I'm using this one in my kernel.

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10KB, 256x134px

>>60895681