Minix2.0/include/limits.h
/* The <limits.h> header defines some basic sizes, both of the language types
* (e.g., the number of bits in an integer), and of the operating system (e.g.
* the number of characters in a file name.
*/
#ifndef _LIMITS_H
#define _LIMITS_H
/* Definitions about chars (8 bits in MINIX, and signed). */
#define CHAR_BIT 8 /* # bits in a char */
#define CHAR_MIN -128 /* minimum value of a char */
#define CHAR_MAX 127 /* maximum value of a char */
#define SCHAR_MIN -128 /* minimum value of a signed char */
#define SCHAR_MAX 127 /* maximum value of a signed char */
#define UCHAR_MAX 255 /* maximum value of an unsigned char */
#define MB_LEN_MAX 1 /* maximum length of a multibyte char */
/* Definitions about shorts (16 bits in MINIX). */
#define SHRT_MIN (-32767-1) /* minimum value of a short */
#define SHRT_MAX 32767 /* maximum value of a short */
#define USHRT_MAX 0xFFFF /* maximum value of unsigned short */
/* _EM_WSIZE is a compiler-generated symbol giving the word size in bytes. */
#if _EM_WSIZE == 2
#define INT_MIN (-32767-1) /* minimum value of a 16-bit int */
#define INT_MAX 32767 /* maximum value of a 16-bit int */
#define UINT_MAX 0xFFFF /* maximum value of an unsigned 16-bit int */
#endif
#if _EM_WSIZE == 4
#define INT_MIN (-2147483647-1) /* minimum value of a 32-bit int */
#define INT_MAX 2147483647 /* maximum value of a 32-bit int */
#define UINT_MAX 0xFFFFFFFF /* maximum value of an unsigned 32-bit int */
#endif
/*Definitions about longs (32 bits in MINIX). */
#define LONG_MIN (-2147483647L-1)/* minimum value of a long */
#define LONG_MAX 2147483647L /* maximum value of a long */
#define ULONG_MAX 0xFFFFFFFFL /* maximum value of an unsigned long */
/* Minimum sizes required by the POSIX P1003.1 standard (Table 2-3). */
#ifdef _POSIX_SOURCE /* these are only visible for POSIX */
#define _POSIX_ARG_MAX 4096 /* exec() may have 4K worth of args */
#define _POSIX_CHILD_MAX 6 /* a process may have 6 children */
#define _POSIX_LINK_MAX 8 /* a file may have 8 links */
#define _POSIX_MAX_CANON 255 /* size of the canonical input queue */
#define _POSIX_MAX_INPUT 255 /* you can type 255 chars ahead */
#define _POSIX_NAME_MAX 14 /* a file name may have 14 chars */
#define _POSIX_NGROUPS_MAX 0 /* supplementary group IDs are optional */
#define _POSIX_OPEN_MAX 16 /* a process may have 16 files open */
#define _POSIX_PATH_MAX 255 /* a pathname may contain 255 chars */
#define _POSIX_PIPE_BUF 512 /* pipes writes of 512 bytes must be atomic */
#define _POSIX_STREAM_MAX 8 /* at least 8 FILEs can be open at once */
#define _POSIX_TZNAME_MAX 3 /* time zone names can be at least 3 chars */
#define _POSIX_SSIZE_MAX 32767 /* read() must support 32767 byte reads */
/* Values actually implemented by MINIX (Tables 2-4, 2-5, 2-6, and 2-7). */
/* Some of these old names had better be defined when not POSIX. */
#define _NO_LIMIT 100 /* arbitrary number; limit not enforced */
#define NGROUPS_MAX 0 /* supplemental group IDs not available */
#if _EM_WSIZE > 2
#define ARG_MAX 16384 /* # bytes of args + environ for exec() */
#else
#define ARG_MAX 4096 /* args + environ on small machines */
#endif
#define CHILD_MAX _NO_LIMIT /* MINIX does not limit children */
#define OPEN_MAX 20 /* # open files a process may have */
#define LINK_MAX 127 /* # links a file may have */
#define MAX_CANON 255 /* size of the canonical input queue */
#define MAX_INPUT 255 /* size of the type-ahead buffer */
#define NAME_MAX 14 /* # chars in a file name */
#define PATH_MAX 255 /* # chars in a path name */
#define PIPE_BUF 7168 /* # bytes in atomic write to a pipe */
#define STREAM_MAX 20 /* must be the same as FOPEN_MAX in stdio.h */
#define TZNAME_MAX 3 /* maximum bytes in a time zone name is 3 */
#define SSIZE_MAX 32767 /* max defined byte count for read() */
#endif /* _POSIX_SOURCE */
#endif /* _LIMITS_H */