My `~/.ssh/config` for Cygwin

# 2023-09-14 «OpenSSH client configuration file (`ssh_config`) syntax»:
Host *
	IdentityFile ~/.ssh/id_rsa
	IdentityFile ~/.ssh/key256
	# 2023-09-14
	# 1) «Sets the number of server alive messages (see below) 
	# which may be sent without ssh(1) receiving any messages back from the server. 
	# If this threshold is reached while server alive messages are being sent, 
	# ssh will disconnect from the server, terminating the session. 
	# It is important to note that the use of server alive messages is very different from TCPKeepAlive (below). 
	# The server alive messages are sent through the encrypted channel and therefore will not be spoofable.
	# The TCP keepalive option enabled by TCPKeepAlive is spoofable. 
	# The server alive mechanism is valuable
	# when the client or server depend on knowing when a connection has become inactive.
	# The default value is 3. 
	# If, for example, ServerAliveInterval (see below) is set to 15 and ServerAliveCountMax is left at the default, 
	# if the server becomes unresponsive, ssh will disconnect after approximately 45 seconds. 
	# This option applies to protocol version 2 only.»
	# 2) «Server alive messages are useful when an SSH server has been configured to close connections
	# after a period of time with no traffic
	# (shared web-hosting providers that offer SSH access almost always do this for example).
	# Setting these two options sends a packet every ServerAliveInterval seconds,
	# for a maximum of ServerAliveCountMax times thus keeping the session alive.»
	ServerAliveCountMax 9999999
	# 2023-09-14
	# 1) «Sets a timeout interval in seconds after which if no data has been received from the server, 
	# ssh(1) will send a message through the encrypted channel to request a response from the server. 
	# The default is 0, indicating that these messages will not be sent to the server. 
	# This option applies to protocol version 2 only.»
	# 2) «Specifies interval for sending keepalive messages to the server.
	# The messages are sent through the encrypted channel,
	# and serve to detect if the server has crashed or the network has gone down.»
	ServerAliveInterval 20
	# 2020-05-11
	# 2023-09-14
	# «Specifies whether to send TCP keepalives to the other side. 
	# These operate on the level of the TCP protocol.
	# Sending keepalives helps properly close the socket when the network or server goes down.
	# On the other hand, without it, the connection may stay alive and any windows open,
	# even if the network is down for a while.»
	# 2023-09-15
	# «Specifies whether the system should send TCP keepalive messages to the other side. 
	# If they are sent, death of the connection or crash of one of the machines will be properly noticed.
	# However, this means that connections will die if the route is down temporarily, and some people find it annoying.
	# The default is ''yes'' (to send TCP keepalive messages),
	# and the client will notice if the network goes down or the remote host dies. 
	# This is important in scripts, and many users want it too.
	# To disable TCP keepalive messages, the value should be set to ''no''.»
	TCPKeepAlive no