[gbhgbh]

I'm trying to store the cache for an application (Unison newsreader) on an external drive rather than keep it in my home directory by using a symbolic link. However I get an error message when I enter the ln -s command. Here are the steps I took.
1. Drag the cache folder to the external drive
2. Delete the original directory
3. Open Terminal App and cd to the external drive
4. Enter the command "ln -s ./Unison/ ~/Library/Cache/Unison/"

However I get this error message
ln: /Users/gbh/Library/Caches/Unison/: No such file or directory

And if I recreate the directory in the path above, I get this error
ln: /Users/gbh/Library/Caches/Unison//: File exists

How can I get this to work?

[Rainy Day]

Using mount may be more appropriate for what you want to do here, particularly with the -o union option. See also man fstab

[Mithras]

Originally posted by gbhgbh:
4. Enter the command "ln -s ./Unison/ ~/Library/Cache/Unison/"

How can I get this to work?

1. Use the full path in both instances.
ln -s /Volumes/ExternalDrive/Unison ~/Library/Caches/Unison

2. Note the lack of the terminal / on the target path.

[Dog Like Nature]

Sounds like the destination for your link doesn't exist.
As Rainy Day says, if the external partition is used solely for your cache, mounting it at the appropriate place in your filesystem would be an elegant option.

Also it's a good idea to specify the source as a full pathname. Using $PWD instead of . can help here.

[gbhgbh]

I got it to work. It was the "/" at the end of the target path that was causing the problem.
Thanks for the help.