# tmux.WarningHandler

- **Module:** tmux
- **Package:** github.com/libtmux/libtmux-go/tmux
- **Language:** Go
- **Kind:** struct
- **Source:** https://github.com/libtmux/libtmux-go/blob/5f808882015a975a65acc7f9da5b3ff0d5cbdc91/tmux/warning.go#L93
- **Page:** https://libtmux.org/reference/go/tmux-warninghandler/

WarningHandler receives warnings synchronously on the caller goroutine:

server, err := tmux.NewServer(tmux.ServerOptions{
	WarningHandler: func(warning tmux.Warning) {
		log.Printf("tmux: %s", warning.Message)
	},
})
if err != nil {
	log.Fatal(err)
}

Operations may invoke it concurrently; synchronize shared state. Diagnostics
may contain caller-supplied arguments and are delivered only to this handler.