LIMITS(4) INTERACTIVE UNIX System LIMITS(4)
NAME
limits - file header for implementation-specific constants
SYNOPSIS
#include <limits.h>
DESCRIPTION
The header file <limits.h> is a list of magnitude limita-
tions imposed by a specific implementation of the operating
system. All values are specified in decimal.
#define ARG_MAX 5120/* max length of arguments to exec */
#define CHAR_BIT 8/* # of bits in a "char" */
#define CHAR_MAX 127/* max integer value of a "char" */
#define CHAR_MIN -128/* min integer value of a "char" */
#define CHILD_MAX 25/* max # of processes per user id */
#define CLK_TCK 100/* # of clock ticks per second */
#define DBL_DIG 16/* digits of precision of a "double" */
#define DBL_MAX 1.79769313486231470e+308/* max decimal value of a "double" */
#define DBL_MIN 4.94065645841246544e-324/* min decimal value of a "double" */
#define FCHR_MAX 1048576/* max size of a file in bytes */
#define FLT_DIG 7/* digits of precision of a "float" */
#define FLT_MAX 3.40282346638528860e+38/* max decimal value of a "float" */
#define FLT_MIN 1.40129846432481707e-45/* min decimal value of a "float" */
#define HUGE_VAL 3.40282346638528860e+38/* error value returned by Math lib */
#define INT_MAX 2147483647/* max decimal value of an "int" */
#define INT_MIN -2147483648/* min decimal value of an "int" */
#define LINK_MAX 1000/* max # of links to a single file */
#define LONG_MAX 2147483647/* max decimal value of a "long" */
#define LONG_MIN -2147483648/* min decimal value of a "long" */
#define NAME_MAX 14/* max # of characters in a file name */
#define OPEN_MAX 60/* max # of files a process can have open */
#define PASS_MAX 8/* max # of characters in a password */
#define PATH_MAX 256/* max # of characters in a path name */
#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 -32768/* min decimal value of a "short" */
#define STD_BLK 1024/* # bytes in a physical I/O block */
#define SYS_NMLN 9/* # of chars in uname-returned strings */
#define UID_MAX 60000/* max value for a user or group ID */
#define USI_MAX 4294967295/* max decimal value of an "unsigned" */
#define WORD_BIT 32/* # of bits in a "word" or "int" */
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