How to set .ssh/config so it can be used on different computers where my username are different?

Question

Host foo
  HostName foo.com
  User specialuser
  IdentityFile /Users/XXX/.ssh/id_rsa

Host *
  User defaultuser

On most machines, my UNIX login user name is XXX. But on one particular machine, it is YYY, how to modify this above .ssh/config file so it can work on all machines?

Answer 1

Try using the %u escape sequence, which expands to the current user's username:

Host foo
HostName foo.com
User specialuser
IdentityFile /Users/%u/.ssh/id_rsa

Host *
User defaultuser

Read under the IdentityFile section in man ssh_config for other escape sequences.