more code

assemblyexample1.asm

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+
+.global _start
+    //exposes a symbol called start to the assembler
+.intel_syntax noprefix
+
+//See: https://www.youtube.com/watch?v=6S5KRJv-7RU
+//See: https://blog.rchapman.org/posts/Linux_System_Call_Table_for_x86_64/
+
+_start:
+    //write call (sys_write)
+    mov rax,1
+        //sys_write system call
+    mov rdi, 1
+        //unsigned int fd = 1 (stdout)
+    lea rsi,[hello_world]
+        //load effective address (lea) into rsi of hello_world data
+    mov rdx, 14
+        //size_t count excluding null terminator
+    syscall
+
+    //exit call
+    mov rax, 60
+    mov rdi, 33 
+    //return result (must be "rdi" not "rdx" - how are these registers named?)
+    syscall 
+    //apprently int 80h interrupt is also syscall?
+
+hello_world:
+    .asciz "Hello, World!\n"
+

assemblytutorial.txt

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+https://www.youtube.com/watch?v=6S5KRJv-7RU
+
+rdi
+rsi
+r8
+r - 64 bit pointer
+
+mov rdi,8
+mov rdi,rsi
+
+memory operations
+
+mov rdi, qword ptr[rsi]  values from memory into register
+mov qword ptr[rsi], rdi  store into memory operation
+
+https://blog.rchapman.org/posts/Linux_System_Call_Table_for_x86_64/
+
+
+Compilation:
+    as -c assemblyexample1.asm -o assemblyexample1.o
+    gcc assemblyexample1.o -o assemblyexample1 -nostdlib -static
+
+Check error code:
+    echo $?