/* file.h  -  Additional file attributes *//* Written 1993 by Werner Almesberger */#ifndef _FILE_H#define _FILE_Htypedef enum { fdt_none,fdt_drop,fdt_undelete } FD_TYPE;typedef struct _fptr {    char name[MSDOS_NAME];    FD_TYPE type;    struct _fptr *first; /* first entry */    struct _fptr *next; /* next file in directory */} FDSC;extern FDSC *fp_root;char *file_name(unsigned char *fixed);/* Returns a pointer to a pretty-printed representation of a fixed MS-DOS file   name. */int file_cvt(unsigned char *name,unsigned char *fixed);/* Converts a pretty-printed file name to the fixed MS-DOS format. Returns a   non-zero integer on success, zero on failure. */void file_add(char *path,FD_TYPE type);/* Define special attributes for a path. TYPE can be either FDT_DROP or   FDT_UNDELETE. */FDSC **file_cd(FDSC **curr,char *fixed);/* Returns a pointer to the directory descriptor of the subdirectory FIXED of   CURR, or NULL if no such subdirectory exists. */FD_TYPE file_type(FDSC **curr,char *fixed);/* Returns the attribute of the file FIXED in directory CURR or FDT_NONE if no   such file exists or if CURR is NULL. */void file_modify(FDSC **curr,char *fixed);/* Performs the necessary operation on the entry of CURR that is named FIXED. */void file_unused(void);/* Displays warnings for all unused file attributes. */#endif