iob.h

操作系统SunOS 4.1.3版本的源码

/*	@(#)iob.h 1.1 92/07/30 SMI	*/

/*
 * This struct keeps track of an open file in the standalone I/O system.
 *
 * It includes an IOB for device addess, an inode, a buffer for reading
 * indirect blocks and inodes, and a buffer for the superblock of the
 * file system (if any).
 */
struct iob {
	struct saioreq  i_si;		/* I/O request block for this file */
	struct inode    i_ino;		/* Inode for this file */
	char            i_buf[MAXBSIZE];/* Buffer for reading inodes & dirs */
	union {
		struct fs ui_fs;	/* Superblock for file system */
		char dummy[SBSIZE];
	}		i_un;
};
#define i_flgs		i_si.si_flgs
#define i_boottab	i_si.si_boottab
#define i_devdata	i_si.si_devdata
#define i_ctlr		i_si.si_ctlr
#define i_unit		i_si.si_unit
#define i_boff		i_si.si_boff
#define i_cyloff	i_si.si_cyloff
#define i_offset	i_si.si_offset
#define i_bn		i_si.si_bn
#define i_ma		i_si.si_ma
#define i_cc		i_si.si_cc
#define i_fs		i_un.ui_fs

#define NBUFS	(NIADDR+1)	/* NOT! a variable */

#define	IOB_UNUSED	0	/* i_flgs field of an unused IOB */
#define	DEV_NAME_LEN	10	/* max device name length */
#define	FILE_NAME_LEN	24	/* max file name length */
#define	SERVER_NAME_LEN	24	/* max. server name length */
#define	PATHNAME_LEN	100	/* max. pathname length */