I want to get the entry point address of a mach-o executable. I have read that otool (-l option) command is able to show us the mach-o entry point. I have tried but i do not see the entry point. I've tried both on 32 and 64 bits executable. If i print the address of main function, i see the 3 last digits are the same between 2 execution. But i see the other digits changing...
otool calls it "entryoff", short for "entry offset" presumably. For example, I compiled curl on my M1 (i.e. ARM) Mac and ran this command:
$ otool -l src/curl | grep entry
entryoff 83892
83892 is 0x147b4 in hexadecimal. Running
objdump -d --macho src/curl | less
and searching for "147b4", we find the _main function:
_main:
1000147b4: ff 03 03 d1 sub sp, sp, #192
1000147b8: fd 7b 0b a9 stp x29, x30, [sp, #176]
1000147bc: fd c3 02 91 add x29, sp, #176
1000147c0: e8 03 01 aa mov x8, x1
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