/* * Copyright (c) 1982, 1986, 1989 Regents of the University of California. * All rights reserved. * * %sccs.include.redist.c% * * @(#)file.h 7.10 (Berkeley) 06/04/91 */ #include #include #ifdef KERNEL /* * Kernel descriptor table. * One entry for each open kernel vnode and socket. */ struct file { struct file *f_filef; /* list of active files */ struct file **f_fileb; /* list of active files */ short f_flag; /* see fcntl.h */ #define DTYPE_VNODE 1 /* file */ #define DTYPE_SOCKET 2 /* communications endpoint */ short f_type; /* descriptor type */ short f_count; /* reference count */ short f_msgcount; /* references from message queue */ struct ucred *f_cred; /* credentials associated with descriptor */ struct fileops { int (*fo_read) __P((struct file *fp, struct uio *uio, struct ucred *cred)); int (*fo_write) __P((struct file *fp, struct uio *uio, struct ucred *cred)); int (*fo_ioctl) __P((struct file *fp, int com, caddr_t data, struct proc *p)); int (*fo_select) __P((struct file *fp, int which, struct proc *p)); int (*fo_close) __P((struct file *fp, struct proc *p)); } *f_ops; off_t f_offset; caddr_t f_data; /* vnode or socket */ }; extern struct file *filehead; /* head of list of open files */ extern int maxfiles; /* kernel limit on number of open files */ extern int nfiles; /* actual number of open files */ #endif /* KERNEL */