/* The 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 */ /*Definitions about long longs (64 bits, may not be supported). */ #ifdef __LONG_LONG_SUPPORTED #define LLONG_MIN (-0x7FFFFFFFFFFFFFFFLL-1) /* minimum value of a * long long */ #define LLONG_MAX 0x7FFFFFFFFFFFFFFFLL /* maximum value of a * long long */ #define ULLONG_MAX 0xFFFFFFFFFFFFFFFFULL /* maximum value of an * unsigned long long */ #endif #include /* 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 DIRSIZ /* max. file name length */ #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 */ #define _POSIX_SYMLOOP_MAX 8 /* The number of symbolic links that can be * traversed in the resolution of a pathname * in the absence of a loop. */ /* 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 262144 /* # 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 30 /* # open files a process may have */ #if 0 /* V1 file system */ #define LINK_MAX CHAR_MAX /* # links a file may have */ #else /* V2 or better file system */ #define LINK_MAX SHRT_MAX /* # links a file may have */ #endif #define MAX_CANON 255 /* size of the canonical input queue */ #define MAX_INPUT 255 /* size of the type-ahead buffer */ #define NAME_MAX DIRSIZ /* # 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() */ #define SYMLOOP_MAX 16 /* maximum number of symbolic links that can * be reliably traversed in the resolution of * a pathname in the absence of a loop. */ #endif /* _POSIX_SOURCE */ #endif /* _LIMITS_H */