Redirecting /dev/null
to stdin will give an immediate EOF
to any read call from that process. This is typically useful to detach a process from a tty (such a process is called a daemon). For example, when starting a background process remotely over ssh, you must redirect stdin to prevent the process waiting for local input.
Another reason to redirect to /dev/null is to prevent an unused file descriptor being created for stdin. This can minimize the total open file handles when you have many long running processes.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…