# ControlReply.number

- **Module:** ControlReply
- **Package:** libtmux-swift
- **Language:** Swift
- **Kind:** property
- **Source:** https://github.com/libtmux/libtmux-swift/blob/f02a4668570e1cc5198c941413750e021f42c214/Sources/LibTmux/ControlProtocol.swift#L71
- **Page:** https://libtmux.org/reference/swift/controlreply-number/

The number tmux stamped on this reply's block.

tmux numbers a command when it runs it, from one counter shared by every
client, so a connection's own replies advance without being contiguous.
A block that does not advance is a protocol violation rather than a
reply, which is what keeps ordering proven rather than assumed.