emacs auto-complete-c-headers and closing brackets

Question

I'm new to Emacs. I followed a tutorial for Emacs as IDE for C/C++ but there are steps that do not work fully for me: the auto-complete for c-headers.

I installed yasnippet and auto-complete for C/C++ headers.

1) I get the normal auto-complete behavior for #include <stdio.h but > closing hook is not added even if I type tab on h .

2) And some functions (I don't know how many) aren't called even with their headers.

Other posts, particularly this one, helped me to solve an issue about #include <float when is not completed with .h, now it works but as alwas tab on h does not add >.

So after changing my .emacs from the link above , #include <ctype.h> doesn't call at least isdig knowing that I want isdigit ... And for getchar it doesn't add ()wherease for while, for loops it works fine...

Here is my new .emacs after following the link above.

; start package.el with emacs
(require 'package)
;add MELPA to repository list
(add-to-list 'package-archives '("melpa" . "http://melpa.org/packages/"))
;initialize package.el
(package-initialize)
;start auto-complete with emacs
(require 'auto-complete)
;do default config for auto-complete
(require 'auto-complete-config)
(ac-config-default)
;start yasineppet with emacs
(require 'yasnippet)
(yas-global-mode 1)
;let's define a function which initializes auto-complete-c-headers and gets called for c/c++ headers hooks
(defun my:ac-c-header-init ()
  (require 'auto-complete-c-headers)
  (add-to-list 'ac-sources 'ac-source-c-headers)
  (setq achead:include-directories
  (append '("/usr/include/c++/5"
        "/usr/include/x86_64-linux-gnu/c++/5"
        "/usr/include/c++/5/backward"
        "/usr/lib/gcc/x86_64-linux-gnu/5/include"
        "/usr/local/include"
        "/usr/lib/gcc/x86_64-linux-gnu/5/include-fixed"
        "/usr/include/x86_64-linux-gnu")
        achead:include-directories)))
;now let's call this function from c/c++ hooks
(add-hook 'c++-mode-hook 'my:ac-c-header-init)
(add-hook 'c-mode-hook 'my:ac-c-header-init)

Something is missing ? The path for headers comes from gcc -xc++ -E -v -

ignoring duplicate directory "/usr/include/x86_64-linux-gnu/c++/5"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/5/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/include/c++/5
 /usr/include/x86_64-linux-gnu/c++/5
 /usr/include/c++/5/backward
 /usr/lib/gcc/x86_64-linux-gnu/5/include
 /usr/local/include
 /usr/lib/gcc/x86_64-linux-gnu/5/include-fixed
 /usr/include/x86_64-linux-gnu
 /usr/include

Answer 1

I'm not sure how you would accomplish this with auto-complete but I do know that you can do all of this and more with company-mode, company-irony, company-irony-c-headers, and irony. You can find all of them on MELPA.

I'll walk you through my init.el file and you can make the relevant changes in yours accordingly. However, you should read the guides of the respective packages on their website instead of just copying mine.

First, enable company-mode using

(add-hook 'after-init-hook #'global-company-mode)

The following are some optimizations that I made. You may or may not want them.

(setq company-idle-delay 0.5)
(setq company-minimum-prefix-length 2)
(setq company-selection-wrap-around t)
(setq company-show-numbers t)
(setq company-tooltip-align-annotations t)

The following line enables irony-mode.

(add-hook 'c-mode-hook #'irony-mode)

I found the following code here and this is supposed to replace the default completion options with the options that irony-mode would provide.

(defun my-irony-mode-hook ()
  (define-key irony-mode-map [remap completion-at-point]
    'irony-completion-at-point-async)
  (define-key irony-mode-map [remap complete-symbol]
    'irony-completion-at-point-async))
(add-hook 'irony-mode-hook #'my-irony-mode-hook)
(add-hook 'irony-mode-hook #'irony-cdb-autosetup-compile-options)

Add company-irony-c-headers and company-irony to the list of backends that company-mode uses.

(eval-after-load 'company
  '(add-to-list
    'company-backends '(company-irony-c-headers company-irony)))