Why is the object(Nasm) file not going to the executable?

Question

GCC

There is a code written in NASM:

global start

    section .data
message: db "Hello, World", 10

    section .text
start:
    mov rax, 0x20000004
    mov rdi, 1
    mov rsi, message
    mov rdx, 13
    syscall
    mov rax, 0x20000001
    xor rdi, rdi
    syscall

I assemble it with the command
nasm -f macho64 file.asm
. I try to turn the resulting file file.o into an executable file with the help of
gcc file.o
which an error is generated:

Undefined symbols for architecture x86_64:
  "_main", referenced from:
     implicit entry/start for main executable
ld: symbol(s) not found for architecture x86_64

Thanks in advance for your reply!

Answer 1

Hold on, but start learning asembler on a poppy, it's kind of cool
; /usr/local/bin/nasm -f macho64 64.asm && ld -macosx_version_min 10.7.0 -lSystem -o 64 64.o && ./64
https://gist.github.com/FiloSottile/7125822
I don't know. Write a makefile, I have everything assembled