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(3alleg), allegro_exit(3alleg), set_uformat(3alleg),
set_config_file(3alleg)