My company package can't auto-complete the keywords of C/C++

Question

When I type the first few letters of some C/C++ keywords, company does't respond until I execute company-keywords.

How could I make company auto complete C/C++ keywords while I type?

Answer 1

There is two variables you can configure to make company behave the way you want:

(setq company-minimum-prefix-length 1)
(setq company-idle-delay 0.1)

This will make company start the completion 0.1 second after you type the first character. You can play with those until you have what you need

Answer 2

I had the same problem. Turns out company mode doesn't use multiple backends unless you group them. Problem occurred because I was adding the 'rtags' backend and it was preferred over company-keywords backend. This is how I fixed it:

(push '(company-rtags company-keywords) company-backends)

Now both backends are used by company mode.