NAME

       ALLEGRO_FILE_INTERFACE - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro.h>

              typedef struct ALLEGRO_FILE_INTERFACE

DESCRIPTION

       A  structure containing function pointers to handle a type of “file”, real or virtual.  See the full dis‐
       cussion in al_set_new_file_interface(3alleg5).

       The fields are:

              void*         (*fi_fopen)(const char *path, const char *mode);
              bool          (*fi_fclose)(ALLEGRO_FILE *f);
              size_t        (*fi_fread)(ALLEGRO_FILE *f, void *ptr, size_t size);
              size_t        (*fi_fwrite)(ALLEGRO_FILE *f, const void *ptr, size_t size);
              bool          (*fi_fflush)(ALLEGRO_FILE *f);
              int64_t       (*fi_ftell)(ALLEGRO_FILE *f);
              bool          (*fi_fseek)(ALLEGRO_FILE *f, int64_t offset, int whence);
              bool          (*fi_feof)(ALLEGRO_FILE *f);
              int           (*fi_ferror)(ALLEGRO_FILE *f);
              const char *  (*fi_ferrmsg)(ALLEGRO_FILE *f);
              void          (*fi_fclearerr)(ALLEGRO_FILE *f);
              int           (*fi_fungetc)(ALLEGRO_FILE *f, int c);
              off_t         (*fi_fsize)(ALLEGRO_FILE *f);

       The fi_open function must allocate memory for whatever userdata structure it needs.  The pointer to  that
       memory  must  be returned; it will then be associated with the file.  The other functions can access that
       data by calling  al_get_file_userdata(3alleg5)  on  the  file  handle.   If  fi_open  returns  NULL  then
       al_fopen(3alleg5) will also return NULL.

       The  fi_fclose  function must clean up and free the userdata, but Allegro will free the ALLEGRO_FILE(3al‐
       leg5) handle.

       If fi_fungetc is NULL, then Allegro’s default implementation of a 16 char long buffer will be used.

Allegro reference manual                                                         ALLEGRO_FILE_INTERFACE(3alleg5)