SVN+SSH, not having to do ssh-add every time? (Mac OS)

First, move your private key file into ~/.ssh. This is not strictly necessary but it's the standard place for such things.

Then run ssh-add -K ~/.ssh/privateKey.txt. It'll prompt for your passphrase if necessary, then add it to your Keychain.

After that, you shouldn't have to do anything else. A slightly longer explanation is available here.

Storing Passphrases in the Keychain

To store the passphrase for your default key in the Keychain open a Terminal and run:

ssh-add -K

And to store the passphrase for a different key run:

ssh-add -K /path/to/private/key/file

When prompted for your passphrase enter it and that is it.

You will never need to run ssh-add nor enter your passphrase again.

Answer taken from this site: http://www-uxsup.csx.cam.ac.uk/~aia21/osx/leopard-ssh.html

After much exploration, I think I've found the answer to this issue completely. First, make sure you do ssh-add -K ~/.ssh/your_key_here. This adds the key to your keychain. Some places, I have read that this is enough, but I wasn't certain. This is also mac-specific, so if you need to do this on another unix flavor, you won't have this option necessarily.

For good measure, I edited the ~/.ssh/config file (you may have to create it) to point to all the keys I have. Mine has the following:

IdentityFile ~/.ssh/identity
IdentityFile ~/.ssh/id_rsa
IdentityFile ~/.ssh/id_dsa 
IdentityFile ~/.ssh/my_other_identity_here
IdentityFile ~/.ssh/yet_another_identity_here

According to the man page for ssh_config, it will try these in order. I'm not sure if the first three default ones I have listed need to be there, but I have included them anyway.