minix/include/sys/types.h
2005-04-21 14:53:53 +00:00

119 lines
4.2 KiB
C
Executable file

/* The <sys/types.h> header contains important data type definitions.
* It is considered good programming practice to use these definitions,
* instead of the underlying base type. By convention, all type names end
* with _t.
*/
#ifndef _TYPES_H
#define _TYPES_H
#ifndef _ANSI_H
#include <ansi.h>
#endif
/* The type size_t holds all results of the sizeof operator. At first glance,
* it seems obvious that it should be an unsigned int, but this is not always
* the case. For example, MINIX-ST (68000) has 32-bit pointers and 16-bit
* integers. When one asks for the size of a 70K struct or array, the result
* requires 17 bits to express, so size_t must be a long type. The type
* ssize_t is the signed version of size_t.
*/
#ifndef _SIZE_T
#define _SIZE_T
typedef unsigned int size_t;
#endif
#ifndef _SSIZE_T
#define _SSIZE_T
typedef int ssize_t;
#endif
#ifndef _TIME_T
#define _TIME_T
typedef long time_t; /* time in sec since 1 Jan 1970 0000 GMT */
#endif
#ifndef _CLOCK_T
#define _CLOCK_T
typedef long clock_t; /* unit for system accounting */
#endif
#ifndef _SIGSET_T
#define _SIGSET_T
typedef unsigned long sigset_t;
#endif
/* Types used in disk, inode, etc. data structures. */
typedef short dev_t; /* holds (major|minor) device pair */
typedef char gid_t; /* group id */
typedef unsigned long ino_t; /* i-node number (V3 filesystem) */
typedef unsigned short mode_t; /* file type and permissions bits */
typedef short nlink_t; /* number of links to a file */
typedef unsigned long off_t; /* offset within a file */
typedef int pid_t; /* process id (must be signed) */
typedef short uid_t; /* user id */
typedef unsigned long zone_t; /* zone number */
typedef unsigned long block_t; /* block number */
typedef unsigned long bit_t; /* bit number in a bit map */
typedef unsigned short zone1_t; /* zone number for V1 file systems */
typedef unsigned short bitchunk_t; /* collection of bits in a bitmap */
typedef unsigned char u8_t; /* 8 bit type */
typedef unsigned short u16_t; /* 16 bit type */
typedef unsigned long u32_t; /* 32 bit type */
typedef char i8_t; /* 8 bit signed type */
typedef short i16_t; /* 16 bit signed type */
typedef long i32_t; /* 32 bit signed type */
typedef struct { u32_t _[2]; } u64_t;
/* The following types are needed because MINIX uses K&R style function
* definitions (for maximum portability). When a short, such as dev_t, is
* passed to a function with a K&R definition, the compiler automatically
* promotes it to an int. The prototype must contain an int as the parameter,
* not a short, because an int is what an old-style function definition
* expects. Thus using dev_t in a prototype would be incorrect. It would be
* sufficient to just use int instead of dev_t in the prototypes, but Dev_t
* is clearer.
*/
typedef int Dev_t;
typedef int Gid_t;
typedef int Nlink_t;
typedef int Uid_t;
typedef int U8_t;
typedef unsigned long U32_t;
typedef int I8_t;
typedef int I16_t;
typedef long I32_t;
/* ANSI C makes writing down the promotion of unsigned types very messy. When
* sizeof(short) == sizeof(int), there is no promotion, so the type stays
* unsigned. When the compiler is not ANSI, there is usually no loss of
* unsignedness, and there are usually no prototypes so the promoted type
* doesn't matter. The use of types like Ino_t is an attempt to use ints
* (which are not promoted) while providing information to the reader.
*/
typedef unsigned long Ino_t;
#if _EM_WSIZE == 2
/*typedef unsigned int Ino_t; Ino_t is now 32 bits */
typedef unsigned int Zone1_t;
typedef unsigned int Bitchunk_t;
typedef unsigned int U16_t;
typedef unsigned int Mode_t;
#else /* _EM_WSIZE == 4, or _EM_WSIZE undefined */
/*typedef int Ino_t; Ino_t is now 32 bits */
typedef int Zone1_t;
typedef int Bitchunk_t;
typedef int U16_t;
typedef int Mode_t;
#endif /* _EM_WSIZE == 2, etc */
/* Signal handler type, e.g. SIG_IGN */
typedef void _PROTOTYPE( (*sighandler_t), (int) );
#endif /* _TYPES_H */