Now that you have a firm grasp of GDB and know what an assembly program looks like, let’s add some complexity. In this chapter, we will show how to obtain the length of a string variable. We will show how to print integer and floating-point values using printf. And we will expand your knowledge of GDB commands.
Listing 4-1 contains the example code that we will use to show how we can find the length of a string and how numeric values are stored in memory.
;alive.asm
section .data
msg1 db "Hello, World!",10,0 ; string with NL and 0
msg1Len equ $-msg1-1 ; ...
