RHSG and IBM disagree on pipe character

https://stylepedia.net/style/#punc-names

The RHSG refers to | as the pipe character, but IBM uses "vertical bar".
If we're just referring to the character, which should we use?

I know it's common and expected to use "pipe" when talking about piping the output of a command or similar to another command, but what about just referring to the char?
