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Why do you say a single word is 2 bytes?

In x86 assembly (and a lot of other contexts), 16 bits are called a word (a left over from 16 bit days when 16 bits were in fact a machine word), and larger data types are named dword (double word, 32 bits), qword (quad word, 64 bits), and so on. This terminology is even included in certain instruction mnemonics (movsb|movsw|movsd, ...).

In ptrace:

> The size of a "word" is determined by the OS variant (e.g., for 32-bit Linux it's 32 bits, etc.).

Taken from http://linux.die.net/man/2/ptrace

On most systems, 1 byte == 8 bits, 1 word == 16 bits, 1 dword (double word) == 32 bits, etc.

This sounds like Windows terminology. I'm pretty sure on 32-bit Linux a word is 32 bits, and ptrace reads 32-bit chunks and not 16-bit chunks.

You're thinking too high-level. We're talking about a "word" in x86 instruction set parlance. It's an artifact of the old 16-bit computing days. Nothing to do with the OS.

I agree that we should't deviate from the subject too much. My reply was intended to fix the generally incorrect comment regarding the size of the word read by ptrace.

In ptrace:

> The size of a "word" is determined by the OS variant (e.g., for 32-bit Linux it's 32 bits, etc.).

Taken from http://linux.die.net/man/2/ptrace

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