types.5

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 5 代码 · 共 72 行

.\" SCCSID: @(#)types.5	8.1	9/11/90
.TH types 5 RISC
.SH Name
types \- primitive system data types
.SH Syntax
.B #include <sys/types.h>
.SH Description
.NXR "type file" "format"
.NXR "system data types" "accessible"
The data 
.PN types 
defined in the include file
are used in UNIX system code.
Some data of these 
.PN types 
are accessible to user code:
.EX 0
#ifndef _TYPES_
#define _TYPES_

/* major part of a device */
#define major(x)        ((int)(((unsigned)(x)>>8)&0377))

/* minor part of a device */
#define minor(x)        ((int)((x)&0377))

/* make a device number */
#define makedev(x,y)    ((dev_t)(((x)<<8) | (y)))

typedef unsigned char   u_char;
typedef unsigned short  u_short;
typedef unsigned int    u_int;
typedef unsigned long   u_long;
typedef unsigned short  ushort;         /* sys III compat */

#ifdef mips
typedef struct  _physadr { int r[1]; } *physadr;
typedef struct  label_t {
        int     val[12];
} label_t;
#endif
typedef struct  _quad { long val[2]; } quad;
typedef long    daddr_t;
typedef char *  caddr_t;
typedef u_long  ino_t;
typedef long    swblk_t;
typedef int     size_t;
typedef int     time_t;
typedef short   dev_t;
typedef int     off_t;

typedef struct  fd_set { int fds_bits[1]; } fd_set;
#endif
.EE
.PP
The form
.I daddr_t
is used for disk addresses except in an
i-node on disk.  For further information, see 
.MS fs 5 .
Times are encoded in seconds since 00:00:00 GMT, January 1, 1970.
The major and minor parts of a device code
specify kind and unit number of a device
and are installation-dependent.
Offsets are measured in bytes from the beginning of a file.
The
.I label_t
variables are used to save the processor state
while another process is running.
.SH See Also
dbx(1), lseek(2), time(3), fs(5)