NAME

types − primitive system data types

SYNOPSIS

#include <sys/types.h>

DESCRIPTION

The data types defined in the include file are used in UNIX system code; some data of these types are accessible to user code:

typedeflong       daddr_t;  /* disk address */
typedefchar *     caddr_t;  /* core address */
typedefunsigned intino_t;     /* i-node number */
typedeflong       time_t;   /* a time */
typedefint        label_t[6]; /* program status */
typedefint        dev_t;    /* device code */
typedeflong       off_t;    /* offset in file */
/* selectors and constructor for device code */
#definemajor(x)  (int)(((unsigned)x>>8))
#defineminor(x)  (int)(x&0377)
#definemakedev(x,y)(dev_t)((x)<<8|(y))

The form daddr_t is used for disk addresses except in an i-node on disk, see filsys(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 label_t variables are used to save the processor state while another process is running. 

SEE ALSO

filsys(5), time(2), lseek(2), adb(1)

7th Edition