See readme.txt for a general introduction, copyright details, and information about how to install Allegro and link your program with it.
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.
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, allegro_exit, set_uformat.
See also: install_allegro, allegro_exit.
See also: install_allegro, allegro_init.
See also: set_gfx_mode, install_sound.
OSTYPE_UNKNOWN - unknown, or regular MSDOS OSTYPE_WIN3 - Windows 3.1 or earlier OSTYPE_WIN95 - Windows 95 OSTYPE_WIN98 - Windows 98 OSTYPE_WINME - Windows ME OSTYPE_WINNT - Windows NT OSTYPE_WIN2000 - Windows 2000 OSTYPE_WINXP - Windows XP OSTYPE_OS2 - OS/2 OSTYPE_WARP - OS/2 Warp 3 OSTYPE_DOSEMU - Linux DOSEMU OSTYPE_OPENDOS - Caldera OpenDOS OSTYPE_LINUX - Linux OSTYPE_SUNOS - SunOS/Solaris OSTYPE_FREEBSD - FreeBSD OSTYPE_DARWIN - Darwin OSTYPE_QNX - QNX OSTYPE_UNIX - Unknown Unix variant OSTYPE_BEOS - BeOS OSTYPE_MACOS - MacOS
See also: allegro_init, os_version, os_multitasking.
See also: os_type, os_multitasking.
See also: os_type, os_version.
See also: set_window_close_button, set_window_close_hook.
On platforms where the close button either does not exist or cannot be disabled, this function returns -1. If this happens, you may wish to use set_window_close_hook() to handle the close event yourself.
When enabling the close button, the function will return the same value for your platform as when disabling. That means it will return non-zero if the button cannot be disabled, even though you are not trying to disable it.
Note that Allegro cannot manipulate the close button of a DOS box in Windows.
See also: set_window_close_hook, set_window_title.
This function should not generally attempt to exit the program or save any data itself. The function could be called at any time, and there is usually a risk of conflict with the main thread of the program. Instead, you should set a flag during this function, and test it on a regular basis in the main loop of the program.
Pass NULL to this function to restore the close button's default functionality. On Windows and BeOS, the following message will appear:
This message will be translated into your selected language if a translation is available in language.dat (see get_config_text()).Warning: forcing program shutdown may lead to data loss and unexpected results. It is preferable to use the exit command inside the window. Proceed anyway? [Yes] [No]
If the user clicks [Yes], the program will exit immediately in the same style as Ctrl+Alt+End (see three_finger_flag).
In other operating systems, the program will exit immediately without prompting the user.
Note that Allegro cannot intercept the close button of a DOS box in Windows.
See also: set_window_close_button, set_window_title, get_config_text, three_finger_flag.
See also: get_desktop_resolution.
See also: desktop_color_depth.
See also: cpu_vendor, cpu_family, cpu_model, cpu_capabilities.
See also: check_cpu, cpu_family, cpu_model, cpu_capabilities.
See also: check_cpu, cpu_vendor, cpu_model, cpu_capabilities.
See also: check_cpu, cpu_vendor, cpu_family, cpu_capabilities.
You can check for multiple features by OR-ing the flags together. For example, to check if the CPU has an FPU and MMX instructions available, you'd do:CPU_ID - Indicates that the "cpuid" instruction is available. If this is set, then all Allegro CPU variables are 100% reliable, otherwise there may be some mistakes. CPU_FPU - An x87 FPU is available. CPU_MMX - Intel MMX instruction set is available. CPU_MMXPLUS - Intel MMX+ instruction set is available. CPU_SSE - Intel SSE instruction set is available. CPU_SSE2 - Intel SSE2 instruction set is available. CPU_3DNOW - AMD 3DNow! instruction set is available. CPU_ENH3DNOW - AMD Enhanced 3DNow! instruction set is available. CPU_CMOV - Pentium Pro "cmov" instruction is available.
if ((cpu_capabilities & (CPU_FPU | CPU_MMX)) == (CPU_FPU | CPU_MMX)) printf("CPU has both an FPU and MMX instructions!\n");
See also: check_cpu, cpu_vendor, cpu_family, cpu_model, cpu_capabilities.