NAME

       install_allegro - Initialise the Allegro library.

SYNOPSIS

       #include <allegro.h>

       int install_allegro(int system_id, int *errno_ptr, int (*atexit_ptr)());

DESCRIPTION

       Initialises  the Allegro library. You must call either this or allegro_init() before doing
       anything other than using the Unicode routines. If you want to use a text mode other  than
       UTF-8,  you  can  set it with set_uformat() before you call this. The other functions that
       can be called before this one  will  be  marked  explicitly  in  the  documentation,  like
       set_config_file().

       The  available system ID codes will vary from one platform to another, but you will almost
       always want to pass SYSTEM_AUTODETECT. Alternatively, SYSTEM_NONE installs a stripped down
       version  of  Allegro  that  won't  even try to touch your hardware or do anything platform
       specific: this can be useful for situations where  you  only  want  to  manipulate  memory
       bitmaps, such as the text mode datafile tools or the Windows GDI interfacing functions.

       The  `errno_ptr' and `atexit_ptr' parameters should point to the errno variable and atexit
       function from your libc: these are required because when Allegro is linked as  a  DLL,  it
       doesn't  have  direct  access  to your local libc data. `atexit_ptr' may be NULL, in which
       case it is your responsibility to call allegro_exit() manually. Example:

          install_allegro(SYSTEM_AUTODETECT, &errno, atexit);

RETURN VALUE

       This function returns zero on success and non-zero on failure (e.g. no system driver could
       be used). Note: in previous versions of Allegro this function would abort on error.

SEE ALSO

       allegro_init(3alleg4),             allegro_exit(3alleg4),            set_uformat(3alleg4),
       set_config_file(3alleg4)