LIMITS(4) RISC/os Reference Manual LIMITS(4)
NAME
limits - header files for implementation-specific constants
SYNOPSIS
#include <limits.h>
#include <float.h>
#include <sys/limits.h>
DESCRIPTION
The header file <limits.h> specifies the sizes of intergral
types as required by the proposed ANSI C standard. The
header file <float.h> specifies the characteristics of
floating types as required by the proposed ANSI C standard.
The constants that refer to long doubles that should appear
in <float.h> are not specified because MIPS does not imple-
ment long doubles. The header file <sys/limits.h> is a list
of magnitude limitations imposed by a specific implementa-
tion of the operating system. All values in the files are
specified in decimal. The file <limits.h> contains:
#define CHAR_BIT 8 /* # of bits in a ``char'' */
#define SCHAR_MIN (-128) /* min integer value of a ``signed char'' */
#define SCHAR_MAX (+127) /* max integer value of a ``signed char'' */
#define UCHAR_MAX 255 /* max integer value of an ``unsigned char'' */
#define CHAR_MIN 0 /* min integer value of a ``char'' */
#define CHAR_MAX 255 /* max integer value of a ``char'' */
#define SHRT_MIN (-32768) /* min decimal value of a ``short'' */
#define SHRT_MAX (+32767) /* max decimal value of a ``short'' */
#define USHRT_MAX 65535 /* max decimal value of an ``unsigned short'' */
#define INT_MIN (-2147483648) /* min decimal value of an ``int'' */
#define INT_MAX (+2147483647) /* max decimal value of a ``int'' */
#define UINT_MAX 4294967295 /* max decimal value of an ``unsigned int'' */
#define LONG_MIN (-2147483648) /* min decimal value of a ``long'' */
#define LONG_MAX (+2147483647) /* max decimal value of a ``long'' */
#define ULONG_MAX 4294967295 /* max decimal value of an ``unsigned long'' */
#define USI_MAX 4294967295 /* max decimal value of an ``unsigned'' */
#define WORD_BIT 32 /* # of bits in a ``word'' or ``int'' */
The file <float.h> contains:
#define FLT_RADIX 2 /* radix of exponent representation */
#define FLT_ROUNDS 1 /* addition rounds (>0 implemention-defined) */
/* number of base-FLT_RADIX digits in the floating point mantissa */
#define FLT_MANT_DIG 24
#define DBL_MANT_DIG 53
/* minimum positive floating-point number x such that 1.0 + x ≠ 1.0 */
#define FLT_EPSILON 1.19209290e-07
#define DBL_EPSILON 2.2204460492503131e-16
/* number of decimal digits of precision */
#define FLT_DIG 6
#define DBL_DIG 15
/* minimum negitive integer such that FLT_RADIX raised to that power
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LIMITS(4) RISC/os Reference Manual LIMITS(4)
minus 1 is a normalized floating point number */
#define FLT_MIN_EXP -125
#define DBL_MIN_EXP -1021
/* minimum normalized positive floating-point number */
#define FLT_MIN 1.17549435e-38
#define DBL_MIN 2.225073858507201e-308
/* minimum negative integer such that 10 raised to that power is
in the range of normalized floating-point numbers */
#define FLT_MIN_10_EXP -37
#define DBL_MIN_10_EXP -307
/* maximum integer such that FLT_RADIX raised to that power
minus 1 is a representable finite floating-point number */
#define FLT_MAX_EXP +128
#define DBL_MAX_EXP +1024
/* maximum representable finite floating-point number */
#define FLT_MAX 3.40282347e+38
#define DBL_MAX 1.797693134862316e+308
/* maximum integer such that 10 raised to that power is
in the range of representable finite floating-point numbers */
#define FLT_MAX_10_EXP +38
#define DBL_MAX_10_EXP +308
The file <sys/limits.h> contains:
#define ARG_MAX 20480 /* max length of arguments to exec */
#define CHILD_MAX 100 /* max # of processes per user id */
#define CLK_TCK 100 /* # of clock ticks per second */
#define FCHR_MAX 2147483647 /* max size of a file in bytes */
#define LINK_MAX 1000 /* max # of links to a single file */
#define PASS_MAX 8 /* max # of characters in a password */
#define PATH_MAX 1024 /* max # of characters in a path name */
#define NAME_MAX PATH_MAX /* max # of characters in a file name */
#define OPEN_MAX 100 /* max # of files a process can have open */
#define PID_MAX 30000 /* max value for a process ID */
#define PIPE_BUF 5120 /* max # bytes atomic in write to a pipe */
#define PIPE_MAX 5120 /* max # bytes written to a pipe in a write */
#define SHRT_MAX 32767 /* max decimal value of a ``short'' */
#define SHRT_MIN -32767 /* min decimal value of a ``short'' */
#define STD_BLK 1024 /* # bytes in a physical I/O block */
#define SYS_NMLN 65 /* # of chars in uname-returned strings */
#define UID_MAX 65536 /* max value for a user or group ID */
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