I have a Python program which uses rlcompleter to provide custom Tab-completion. The completion works when it is run under a bash terminal. However, it does not work under emacs, in shell mode, nor in eshell mode.
I noticed that Tab is really bound to completion-at-point, eshell-pcomplete, and so on, so I tried an (insert "\t"), supposing that this would trigger the completion, which I understand happens when the child process reads a "\t" character. But this does not work either. Perhaps input is buffered until a "RET"?
Completion for commands like service, which define their own candidates, does not work as expected either.
How can I access these candidates within Emacs?
Try using
M-x ansi-term. I find it behaves a bit more like what I have come to expect from a *nix terminal.