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Update 2024-07-27-sys-write-string.md

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2024-07-27-sys-write-string.md
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@ -12,7 +12,7 @@ An approachable way for beginners to understand how syscalls are made in Linux i
Looking at that table, it can be concluded the following registers need to be populated: Looking at that table, it can be concluded the following registers need to be populated:
- `rdi` → the call identifier. for `sys_write`, it's `1` from reading the first column of that table - `rax` → the call identifier. for `sys_write`, it's `1` from reading the first column of that table
- `rdi` → file descriptor, `1` being for `stdout` - `rdi` → file descriptor, `1` being for `stdout`
- `rsi` → contents of buffer (i.e. the string) - `rsi` → contents of buffer (i.e. the string)
- `rdx` → length of the buffer for stdout - `rdx` → length of the buffer for stdout
@ -23,7 +23,7 @@ The first step is to define the `.data` section and initialize memory for `rsi`.
The syntax looks like this: The syntax looks like this:
<variable name> <type> <value> <variable name> <type> <value>
`0xa` is just the ASCII hex representation of a new line. `0x0a` is just the ASCII hex representation of a new line.
``` ```
; sys_write_string.asm ; sys_write_string.asm