This chapter describes constants (defined names) and their values.
The values of defined names in this chapter are provided for
reference only; they may change in future releases.
They are especially valuable when debugging, when
the name might not be available.
_access Mode Values
Declared in: 
io.h
_bios_disk Service Values
Declared in: 
bios.h
| Name | Value | Meaning | 
|---|
| _DISK_RESET | 0 | Hard reset | 
| _DISK_STATUS | 1 | Retrieve status | 
| _DISK_READ | 2 | Read sectors | 
| _DISK_WRITE | 3 | Write sectors | 
| _DISK_VERIFY | 4 | Verify disk readability | 
| _DISK_FORMAT | 5 | Format track | 
_bios_keybrd Service Values
Declared in: 
bios.h
| Name | Value | Meaning | 
|---|
| _KEYBRD_READ | 0x00 | Keyboard read | 
| _KEYBRD_READY | 0x01 | Is keystroke available? | 
| _KEYBRD_SHIFTSTATUS | 0x02 | Retrieve shift key status | 
| _NKEYBRD_READ | 0x10 | Enhanced read | 
| _NKEYBRD_READY | 0x11 | Enhanced ready | 
| _NKEYBRD_SHIFTSTATUS | 0x12 | Enhanced shift status | 
_bios_printer Service Values
Declared in: 
bios.h
| Name | Value | Meaning | 
|---|
| _PRINTER_WRITE | 0 | Write data to printer | 
| _PRINTER_INIT | 1 | Initialize printer | 
| _PRINTER_STATUS | 2 | Retrieve printer status | 
_bios_serialcom Service Values
Declared in: 
bios.h
| Name | Value | Meaning | 
|---|
| _COM_INIT | 0 | Initialize port | 
| _COM_SEND | 1 | Send data | 
| _COM_RECEIVE | 2 | Receive data | 
| _COM_STATUS | 3 | Request status | 
_bios_serialcom Data Values
Declared in: 
bios.h
| Name | Value | Meaning | 
|---|
| _COM_110 | 0x00 | 110 baud | 
| _COM_NOPARITY | 0x00 | No parity | 
| _COM_STOP1 | 0x00 | 1 stop bit | 
| _COM_CHR7 | `             0x02 | 7 data bits | 
| _COM_CHR8 | 0x03 | 8 data bits | 
| _COM_STOP2 | 0x04 | 2 stop bits | 
| _COM_ODDPARITY | 0x08 | Odd parity | 
| _COM_EVENPARITY | 0x18 | Even parity | 
| _COM_150 | 0x20 | 150 baud | 
| _COM_300 | 0x40 | 300 baud | 
| _COM_600 | 0x60 | 600 baud | 
| _COM_1200 | 0x80 | 1200 baud | 
| _COM_2400 | 0xa0 | 2400 baud | 
| _COM_4800 | 0xc0 | 4800 baud | 
| _COM_9600 | 0xe0 | 9600 baud | 
_bios_timeofday Service Values
Declared in: 
bios.h
| Name | Value | Meaning | 
|---|
| _TIME_GETCLOCK | 0 | Retrieve time | 
| _TIME_SETCLOCK | 1 | Set time | 
clock Values
Declared in: time.h
To convert from ticks to seconds, divide the clock_t value
returned from the clock function by CLOCKS_PER_SEC.
| Name | Value | Meaning | 
|---|
| CLOCKS_PER_SEC | 100 | Number of timer ticks per second | 
| CLK_TCK | 100 | Synonym of CLOCKS_PER_SEC | 
cpumode Values
Declared in: stdlib.h
| Name | Value | Meaning | 
|---|
| _REAL_MODE | 0 | Running in real mode | 
| _PROT_MODE | 1 | Running in protected mode | 
disp_setattr Display Attribute Values
Declared in: disp.h
| Name | Value | Meaning | 
|---|
| DISP_NONDISPLAY | 0x00 | Non-displaying attribute | 
| DISP_UNDERLINE | 0x01 | Underline attribute | 
| DISP_NORMAL | 0x07 | Normal attribute | 
| DISP_INTENSITY | 0x08 | Intensity attribute | 
| DISP-REVERSEVIDEO | 0x70 | Reverse video attribute | 
| DISP_BLINK | 0x80 | Blink attribute | 
disp_setcursortype Standard Cursor Types
Declared in: disp.h
For monochrome/ color values:
| Name | Value | Meaning | 
|---|
| DISP_CURSORBLOCK | 0x000c/0x0007 | Block cursor | 
| DISP_CURSORHALF | 0x060c/0x0307 | Half cursor | 
| DISP_CURSORUL | 0x0b0c/0x0707 | Underline cursor | 
EMM Page Size
Declared in: emm.h
| Name | Value | Meaning | 
|---|
EMM_PAGESIZE,    0x4000,          Size of an EMM page
errno Values
Declared in: errno.h and other header files
| Name | Value | Meaning | 
|---|
| EZERO | 0 | No error | 
| EPERM | 1 | Operation not permitted | 
| ENOENT | 2 | No such file or directory | 
| ESRCH | 3 | No such process | 
| EINTR | 4 | Interrupted function call | 
| EIO | 5 | Input/ output error | 
| ENXIO | 6 | No such device or address | 
| E2BIG | 7 | Argument list too long | 
| ENOEXEC | 8 | Exec format error | 
| EBADF | 9 | Bad file descriptor | 
| ECHILD | 10 | No child processes | 
| EAGAIN | 11 | Resource temporarily unavailable | 
| ENOMEM | 12 | Not enough space | 
| EACCES | 13 | Permission denied | 
| EFAULT | 14 | Bad address | 
| EBUSY | 16 | Resource device | 
| EEXIST | 17 | File exists | 
| EXDEV | 18 | Improper link | 
| ENODEV | 19 | No such device | 
| ENOTDIR | 20 | Not a directory | 
| EISDIR | 21 | Is a directory | 
| EINVAL | 22 | Invalid argument | 
| ENFILE | 23 | Too many open files in system | 
| EMFILE | 24 | Too many open files | 
| ENOTTY | 25 | Inappropriate I/ O control operation | 
| EFBIG | 27 | File too large | 
| ENOSPC | 28 | No space left on device | 
| ESPIPE | 29 | Invalid seek | 
| EROFS | 30 | Read-only file system | 
| EMLINK | 31 | Too many links | 
| EPIPE | 32 | Broken pipe | 
| EDOM | 33 | Domain error | 
| ERANGE | 34 | Result too large | 
| EDEADLK | 36 | Resource deadlock avoided | 
| EDEADLOCK | 36 | Synonym of EDEADLK | 
| ENAMETOOLONG | 38 | Filename too long | 
| ENOLCK | 39 | No locks available | 
| ENOSYS | 40 | Function not implemented | 
| ENOTEMPTY | 41 | Directory not empty | 
| EILSEQ | 42 | Illegal byte sequence | 
exit ANSI-Standard Return Values
Declared in: stdlib.h
| Name | Value | Meaning | 
|---|
| EXIT_SUCCESS | 0 | Successful termination | 
| EXIT_FAILURE | 1 | Unsuccessful termination | 
File Attributes
Declared in: dos.h
Several functions,, including _dos_creat and _dos_findfirst,
use these attributes. Note that some values, which can be used when
searching, cannot be used when creating a file. Examples are
_A_VOLID and _A_SUBDIR: a volume ID or a subdirectory cannot
be created with _dos_creat, only a file can be created.
| Name | Value | Meaning | 
|---|
| _A_NORMAL | 0x00 | Normal file | 
| _A_RDONLY | 0x01 | Read-only file | 
| _A_HIDDEN | 0x02 | Hidden file | 
| _A_SYSTEM | 0x04 | System file | 
| _A_VOLID | 0x08 | Volume ID | 
| _A_SUBDIR | 0x10 | Subdirectory | 
| _A_ARCH | 0x20 | File changed since last archive | 
| FA_NORMAL | 0x00 | Synonym of _A_NORMAL | 
| FA_RDONLY | 0x01 | Synonym of _A_RDONLY | 
| FA_HIDDEN | 0x02 | Synonym of _A_HIDDEN | 
| FA_SYSTEM | 0x04 | Synonym of _A_SYSTEM | 
| FA_LABEL | 0x08 | Synonym of _A_VOLID | 
| FA_DIREC | 0x10 | Synonym of _A_SUBDIR | 
| FA_ARCH | 0x20 | Synonym of _A_ARCH | 
Floating-Point Number Classifications
Declared in: fltpnt.h
| Name | Value | Meaning | 
|---|
| FP_NANS | 0 | Signaling NaN | 
| FP_NANQ | 1 | Quiet NaN | 
| FP_INFINITE | 2 | Infinity | 
| FP_NORMAL | 3 | Any number not covered by other classifications | 
| FP_SUBNORMAL | 4 | Subnormal or denormal | 
| FP_ZERO | 5 | Zero | 
Floating-Point Exceptions
Declared in: fltenv.h
| Name | Value | Meaning | 
|---|
| FE_INVALID | 0x01 | Invalid operand or operation | 
| FE_DIVBYZERO | 0x04 | Divide by zero | 
| FE_OVERFLOW | 0x08 | Overflow | 
| FE_UNDERFLOW | 0x10 | Underflow | 
| FE_INEXACT | 0x20 | Inexact result | 
| FE_ALL_EXCEPT | 0x3F | All exceptions | 
Floating-Point Precision Values
Declared in: fltenv.h
| Name | Value | Meaning | 
|---|
| FE_FLTPREC | 0x0000 | Use float (32-bit) precision | 
| FE_DBLPREC | 0x0200 | Use double (64-bit) precision | 
| FE_LDBLPREC | 0x0300 | Use long double (80-bit) precision | 
Floating-Point Rounding Values
Declared in: fltenv.h
| Name | Value | Meaning | 
|---|
| FE_TONEAREST | 0x0000 | Round to nearest value | 
| FE_DOWNWARD | 0x0400 | Round toward negative infinity | 
| FE_UPWARD | 0x0800 | Round toward positive infinity | 
| FE_TOWARDZERO | 0x0c00 | Round toward zero (drop fractional part) | 
Floating-Point Special Values
Declared in: fltenv.h
| Name | Meaning | 
|---|
| INFINITY | The value of positive infinity | 
| NAN | The value of a quiet NaN | 
| NANS | The value of a signaling NaN | 
Floating-Point Characteristic Constants
Declared in: 
float.h
| Name | Value | Meaning | 
|---|
| DBL_MIN_EXP | -1021 | Smallest exponent
                                                        value for a double,
                                                        using base
                                                        FLT_RADIX | 
| LDBL_MIN_EXP | -1021 | Smallest exponent
                                                        value for a long
                                                        double, using base
                                                        FLT_RADIX | 
| DBL_DIG | 15 | Number of decimal
                                                        digits accurately
                                                        represented by a
                                                        double | 
| DBL_EPSILON | 2.2204460492501131e-16 | Smallest difference between two doubles | 
| DBL_MANT_DIG | 53 | Number of
                                                        base-FLT_RADIX
                                                        digits in the
                                                        significand of a
                                                        double (number of
                                                        binary digits in the
                                                        significand) | 
| DBL_MAX | 1.7976931348623157e+308 | Largest positive value
                                                        represented by a double | 
| DBL_MAX_10_EXP | 308 | Largest exponent for
                                                        a double, using base
                                                        10 | 
| DBL_MAX_EXP | 1024 | Largest exponent
                                                        value for a double,
                                                        using base
                                                        FLT_RADIX | 
| DBL_MIN | 2.225073855072014e-308 | Smallest positive
                                                        value represented by
                                                        a double | 
| DBL_MIN_10_EXP | -307 | Smallest exponent
                                                        for a double, using
                                                        base 10 | 
| FLT_DIG | 6 | Number of decimal
                                                        digitals represented
                                                        by a float | 
| FLT_EPSILON | 1.1920929e-7f | Smallest difference
                                                        between two floats | 
| FLT_MANT_DIG | 24 | Number of base
                                                        FLT_RADIX digits in
                                                        significand of float
                                                        (number of binary
                                                        digits in significand) | 
| FLT_MAX | 3.402823466e+38F | Largest positive value
                                                        represented by a float | 
| FLT_MAX_10_EXP | 38 | Largest exponent
                                                        value for a float,
                                                        using base 10 | 
| FLT_MAX_EXP | 128 | Largest exponent
                                                        value for a float,
                                                        using base FLT_RADIX | 
| FLT_MIN | 1.175494351e-38 | Smallest positive
                                                        value represented by a float | 
| FLT_MIN_10_EXP | -37 | Smallest exponent
                                                        value for a float,
                                                        using base 10 | 
| FLT_MIN_EXP | -125 | Smallest exponent
                                                        value for a float,
                                                        using base FLT_RADIX | 
| FLT_RADIX | 2 | Radix used to represent floating point numbers | 
| LDBL_DIG | 15 | Number of decimal digits represented by
                                                        a long double | 
| LDBL_EPSILON | 2.2204460492501131e-16 | Smallest difference
                                                        between two long doubles | 
| LDBL_MANT_DIG | 53 | Number of base
                                                        FLT_RADIX digits in
                                                        significand of a long
                                                        double (number of
                                                        binary digits in
                                                        significand) | 
| LDBL_MAX | 1.7976931348623157e+308 | Largest positive value
                                                        represented by a
                                                        long double | 
| LDBL_MAX_10_EXP | 308 | Largest exponent
                                                        value for a long
                                                        double, using base 10 | 
| LDBL_MAX_EXP | 1024 | Largest exponent
                                                        value for a long
                                                        double, using base
                                                        FLT_RADIX | 
| LDBL_MIN | 2.2250738585072014e-308 | Smallest positive
                                                        value represented by
                                                        a long double | 
| LDBL_MIN_10_EXP | -307 | Smallest exponent
                                                        value for a long
                                                        double, using base 10 | 
fnsplit Return Values
Declared in: dir.h
| Name | Value | Meaning | 
|---|
| EXTENSION | 0x02 | An extension was found | 
| FILENAME | 0x04 | A filename was found | 
| DIRECTORY | 0x08 | A directory was found | 
| DRIVE | 0x10 | A drive was found | 
fnsplit Maximum Size of Components
Declared in: dir.h
| Name | Value | Meaning | 
|---|
| MAXDRIVE | 3 | Largest drive identifier | 
| MAXEXT | 5 | Largest extension | 
| MAXFILE | 6 | Largest filename | 
| MAXDIR | 66 | Largest directory name | 
| MAXPATH | 80 | Largest pathname | 
_getch and _getche Extended Key Codes
Declared in: conio.h
To return a key with no ASCII value, such as a function key, _getch
returns a 0 or 0xe0 followed by one of these codes: 
| Name | Value | Meaning | 
|---|
| _KB_BACK_TAB | 15 | Backtab | 
| _KB_F1 | 59 | F1 | 
| _KB_F2 | 60 | F2 | 
| _KB_F3 | 61 | F3 | 
| _KB_F4 | 62 | F4 | 
| _KB_F5 | 63 | F5 | 
| _KB_F6 | 64 | F6 | 
| _KB_F7 | 65 | F7 | 
| _KB_F8 | 66 | F8 | 
| _KB_F9 | 67 | F9 | 
| _KB_F10 | 68 | F10 | 
| _KB_HOME | 71 | Home | 
| _KB_UP | 72 | Up arrow | 
| _KB_PGUP | 73 | Page up | 
| _KB_LEFT | 75 | Left arrow | 
| _KB_RIGHT | 77 | Right arrow | 
| _KB_END | 79 | End | 
| _KB_DOWN | 80 | Down arrow | 
| _KB_PGDN | 81 | Page down | 
| _KB_INS | 82 | Insert | 
| _KB_DEL | 83 | Delete | 
| _KB_SF1 | 84 | Shift-F1 | 
| _KB_SF2 | 85 | Shift-F2 | 
| _KB_SF3 | 86 | Shift-F3 | 
| _KB_SF4 | 87 | Shift-F4 | 
| _KB_SF5 | 88 | Shift-F5 | 
| _KB_SF6 | 89 | Shift-F6 | 
| _KB_SF7 | 90 | Shift-F7 | 
| _KB_SF8 | 91 | Shift-F8 | 
| _KB_SF9 | 92 | Shift-F9 | 
| _KB_SF10 | 93 | Shift-F10 | 
| _KB_CF1 | 94 | Control-F1 | 
| _KB_CF2 | 95 | Control-F2 | 
| _KB_CF3 | 96 | Control-F3 | 
| _KB_CF4 | 97 | Control-F4 | 
| _KB_CF5 | 98 | Control-F5 | 
| _KB_CF6 | 99 | Control-F6 | 
| _KB_CF7 | 100 | Control-F7 | 
| _KB_CF8 | 101 | Control-F8 | 
| _KB_CF9 | 102 | Control-F9 | 
| _KB_CF10 | 103 | Control-F10 | 
| _KB_AF1 | 104 | Alt-F1 | 
| _KB_AF2 | 105 | Alt-F2 | 
| _KB_AF3 | 106 | Alt-F3 | 
| _KB_AF4 | 107 | Alt-F4 | 
| _KB_AF5 | 108 | Alt-F5 | 
| _KB_AF6 | 109 | Alt-F6 | 
| _KB_AF7 | 110 | Alt-F7 | 
| _KB_AF8 | 111 | Alt-F8 | 
| _KB_AF9 | 112 | Alt-F9 | 
| _KB_AF10 | 113 | Alt-F10 | 
| _KB_CLEFT | 115 | Control-left arrow | 
| _KB_CRIGHT | 116 | Control-right arrow | 
| _KB_CEND | 117 | Control-end | 
| _KB_CPGDN | 118 | Control-page down | 
| _KB_CHOME | 119 | Control-home | 
| _KB_A1 | 120 | Alt-1 | 
| _KB_A2 | 121 | Alt-2 | 
| _KB_A3 | 122 | Alt-3 | 
| _KB_A4 | 123 | Alt-4 | 
| _KB_A5 | 124 | Alt-5 | 
| _KB_A6 | 125 | Alt-6 | 
| _KB_A7 | 126 | Alt-7 | 
| _KB_A8 | 127 | Alt-8 | 
| _KB_A9 | 128 | Alt-9 | 
| _KB_A0 | 129 | Alt-0 | 
| _KB_AMINUS | 130 | Alt-minus | 
| _KB_APLUS | 131 | Alt-plus | 
| _KB_CPGUP | 132 | Control-page up | 
_hardresume Result Codes
Declared in: dos.h
| Name | Value | Meaning | 
|---|
| _HARDERR_IGNORE | 0 | Ignore error | 
| _HARDERR_RETRY | 1 | Retry operation | 
| _HARDERR_ABORT | 2 | Abort program | 
| _HARDERR_FAIL | 3 | Fail system call | 
HUGE_VAL
Declared in: math.h
| Name | Value | Meaning | 
|---|
| HUGE_VAL | infinity | Double value represents overflow | 
Integer Sizes
Declared in: limits.h
| Name | Value | Meaning | 
|---|
| CHAR_BIT | 8 | Number of bits in char | 
| CHAR_MAX | 255 or 127 | Largest char, depends on sign | 
| CHAR_MIN | 0 or -127 | Smallest char, depends on sign | 
| INT_MAX | 2147483647 or 32767 | Largest int, depends on size | 
| INT_MIN | -2147483647 or -32767 | Smallest int, depends on size | 
| LONG_MAX | 2147483647 | Largest long | 
| LONG_MIN | -2147483647 | Smallest long | 
| MB_LEN_MAX | 2 | Longest multi-byte char | 
| SCHAR_MAX | 127 | Largest signed char | 
| SCHAR_MIN | -127 | Smallest signed char | 
| SHRT_MAX | 32767 | Largest short | 
| SHRT_MIN | -32767 | Smallest short | 
| UCHAR_MAX | 255 | Largest unsigned char | 
| UINT_MAX | 65535 or 4294967295 | Largest unsigned int, depends on size | 
| USHRT_MAX | 65535 | Largest unsigned short | 
_locking Mode Values
Declared in: sys\locking.h
| Name | Value | Meaning | 
|---|
| _LK_UNLCK | 0 | Unlock | 
| _LK_LOCK | 1 | Lock with retry | 
| _LK_NBLCK | 2 | Lock without retry | 
| _LK_RLCK | 3 | Same as _LK_LOCK | 
| _LK_NBRLCK | 4 | Same as _LK_NBLCK | 
| LK_UNLCK | 0 | Synonym of _LK_UNLCK | 
| LK_LOCK | 1 | Synonym of _LK_LOCK | 
| LK_NBLCK | 2 | Synonym of _LK_NBLCK | 
| LK_RLCK | 3 | Synonym of _LK_RLCK | 
| LK_NBRLCK | 4 | Synonym of _LK_NBRLCK | 
_matherr Exception Types
Declared in: math.h
| Name | Value | Meaning | 
|---|
| _DOMAIN | 1 | Domain error | 
| _SIGN | 2 | Argument singularity | 
| _OVERFLOW | 3 | Overflow range error | 
| _UNDERFLOW | 4 | Result too small | 
| _TLOSS | 5 | Total loss of significance | 
| _PLOSS | 6 | Partial loss of significance | 
| DOMAIN | 1 | Synonym of _DOMAIN | 
| SING | 2 | Synonym of _SING | 
| OVERFLOW | 3 | Synonym of _OVERFLOW | 
| UNDERFLOW | 4 | Synonym of _UNDERFLOW | 
| TLOSS | 5 | Synonym of _TLOSS | 
| PLOSS | 6 | Synonym of _PLOSS | 
Multi-byte Characters
Declared in: stdlib.h
| Name | Value | Meaning | 
|---|
| MB_CUR_MAX | 1 | Largest number of bytes in a multi-byte character for the current locale | 
_open Flag Values
Declared in: fcntl.h
| Name | Value | Meaning | 
|---|
| _O_RDONLY | 0x0000 | Read from file only | 
| _O_WRONLY | 0x0001 | Write to file only | 
| _O_RDWR | 0x0002 | Read and write from file | 
| _O_APPEND | 0x0008 | Write only at end of file | 
| _O_CREAT | 0x0100 | Create the file | 
| _O_TRUNC | 0x0200 | Truncate file | 
| _O_EXCL | 0x0400 | Fail if file exists | 
| _O_TEXT | 0x4000 | Use translated mode | 
| _O_BINARY | 0x8000 | Use untranslated mode | 
| O_RDONLY | 0x0000 | Synonym of _O_RDONLY | 
| O_WRONLY | 0x0001 | Synonym of _O_WRONLY | 
| O_RDWR | 0x0002 | Synonym of _O_RDWR | 
| O_APPEND | 0x0008 | Synonym of _O_APPEND | 
| O_CREAT | 0x0100 | Synonym of _O_CREAT | 
| O_TRUNC | 0x0200 | Synonym of _O_TRUNC | 
| O_EXCL | 0x0400 | Synonym of _O_EXCL | 
| O_TEXT | 0x4000 | Synonym of _O_TEXT | 
| O_BINARY | 0x8000 | Synonym of _O_BINARY | 
| _O_RAW | 0x8000 | Synonym of _O_BINARY | 
_osmode Values
Declared in: stdlib.h
| Name | Value | Meaning | 
|---|
| _DOS_MODE | 0 | DOS is running | 
| _WIN_MODE | 2 | Windows is running | 
Random Numbers
Declared in: stdlib.h
| Name | Value | Meaning | 
|---|
| RAND_MAX | 32767 | Largest number returned by the rand function | 
Seek Origins
Declared in: io.h and stdio.h
Seek origins are used by fseek and _lseek.
| Name | Value | Meaning | 
|---|
| SEEK_SET | 0 | Seek relative to beginning of file | 
| SEEK_CUR | 1 | Seek relative to current position | 
| SEEK_END | 2 | Seek relative to end of file | 
setlocal Categories
Declared in: locale.h
| Name | Value | Meaning | 
|---|
| LC_ALL | 0 | All categories | 
| LC_COLLATE | 1 | Collating sequence | 
| LC_CTYPE | 2 | Character types | 
| LC_MONETARY | 3 | Monetary formatting | 
| LC_NUMERIC | 4 | Number formatting | 
| LC_TIME | 5 | Time formatting | 
setvbuf Modes
Declared in: stdio.h
| Name | Value | Meaning | 
|---|
| _IOFBF | 0x0000 | Full buffering | 
| _IONBF | 0x0004 | No buffering | 
| _IOLBF | 0x0040 | Line buffering | 
signal Codes
Declared in: signal.h
| Name | Value | Meaning | 
|---|
| SIGINT | 2 | Interrupt | 
| SIGILL | 4 | Illegal instruction | 
| SIGBREAK | 6 | Control-break | 
| SIGFPE | 8 | Math error | 
| SIGSEGV | 11 | Segmentation violation | 
| SIGTERM | 15 | Program termination request | 
| SIGABRT | 22 | Abnormal termination | 
| NSIG | 23 | The number of signals | 
signal Functions
Declared in: signal.h
| Name | Value | Meaning | 
|---|
| SIG_ERR | -1 | Signal could not be handled | 
| SIG_DFL | 0 | Default signal handling | 
| SIG_IGN | 1 | Ignore signal | 
_sopen Sharing Flag Values
Declared in: share.h
| Name | Value | Meaning | 
|---|
| _SH_COMPAT | 0x00 | Compatibility mode | 
| _SH_DENYRW | 0x10 | Deny all access while file is open | 
| _SH_DENYWR | 0x20 | Deny write access while file is open | 
| _SH_DENYRD | 0x30 | Deny read access while file is open | 
| _SH_DENYNO | 0x40 | Allow read/ write access while file is open | 
| SH_COMPAT | 0x00 | Synonym of _SH_COMPAT | 
| SH_DENYRW | 0x10 | Synonym of _SH_DENYRW | 
| SH_DENYWR | 0x20 | Synonym of _SH_DENYWR | 
| SH_DENYRD | 0x30 | Synonym of _SH_DENYRD | 
| SH_DENYNO | 0x40 | Synonym of _SH_DENYNO | 
spawn Modes
Declared in: process.h
| Name | Value | Meaning | 
|---|
| _P_WAIT | 0 | Wait for child process to complate | 
| _P_OVERLAY | 2 | Replace current process with child process | 
| P_WAIT | 0 | Synonym of _P_WAIT | 
| P_OVERLAY | 2 | Synonym of _P_OVERLAY | 
_splitpath Buffer Sizes
Declared in: stdlib.h
| Name | Value | Meaning | 
|---|
| _MAX_DIR | 256 | Largest directory | 
| _MAX_EXT | 256 | Largest extension | 
| _MAX_FNAME | 256 | Largest filename | 
| _MAX_PATH | 260 | Largest path | 
| _MAX_DRIVE | 3 | Largest drive | 
_stat st_mode Values
Declared in: sys\stat.h
| Name | Value | Meaning | 
|---|
| _S_IEXEC | 0x0040 | Handle refers to an executable file | 
| _S_IWRITE | 0x0080 | Path or handle refers to a writable file | 
| _S_IREAD | 0x0100 | Path or handle refers to a readable file | 
| _S_IFCHR | 0x2000 | Handle refers to a character device | 
| _S_IFDIR | 0x4000 | Path refers to a directory | 
| _S_IFREG | 0x8000 | Path or handle refers to a regular file | 
| S_IEXEC | 0x0040 | Synonym of _S_IEXEC | 
| S_IREAD | 0x0100 | Synonym of _S_IREAD | 
| S_IFCHR | 0x2000 | Synonym of _S_IFCHR | 
| S_IFIDR | 0x4000 | Synonym of _S_IFDIR | 
| S_IFREG | 0x8000 | Synonym of _S_IFREG | 
stdio.h Miscellaneous Values
Declared in: 
stdio.h
| Name | Value | Meaning | 
|---|
| EOF | -1 | End of file value | 
| FOPEN_MAX | 20 | Largest number of files that can be open at once | 
| _NFILE | 40 or 60 | Number of file handles | 
| FILENAME_MAX | 79 | Largest filename | 
| BUFSIZ | 0x4000 | Size of a buffer used by setbuf | 
Swap Error Codes
Declared in: swap.h
| Name | Value | Meaning | 
|---|
| SWAP_FREEMEMERROR | -2 | DOS refuses to shrink the primary memory block allocated for the program | 
| SWAP_NOVMSPACE | -3 | Disk drive has no room to write program's image | 
Temporary Files
Declared in: stdio.h
| Name | Value | Meaning | 
|---|
| P_tmpdir | "\\" | Directory used for temporary files by tmpnam function | 
| L_tmpnam | 16 | Largest filename generated by tmpfile function | 
| TMP_MAX | 32767 | Largest number of unique file names generated by tmpnam function | 
tsr_install Arguments
Declared in: 
tsr.h
| Name | Value | Meaning | 
|---|
| TIMESLICE | 1 | Timeslice TSR | 
| TSR_DEBUG | 2 | Debug TSR | 
| POPONLY |  | Popup TSR | 
TSR Scancodes
Declared in: 
tsr.h
| Name | Value | Meaning | 
|---|
| NO_SCAN | 0 | No scancode | 
| RSHIFT | 1 | Right shift | 
| LSHIFT | 2 | Left shift | 
| CTRL | 4 | Control | 
| ALT | 8 | Alt | 
| SCAN_Q | 16 | Q | 
| SCAN_W | 17 | W | 
| SCAN_E | 18 | E | 
| SCAN_R | 19 | R | 
| SCAN_T | 20 | T | 
| SCAN_Y | 21 | Y | 
| SCAN_U | 22 | U | 
| SCAN_I | 23 | I | 
| SCAN_O | 24 | O | 
| SCAN_P | 25 | P | 
| SCAN_A | 30 | A | 
| SCAN_S | 31 | S | 
| SCAN_D | 32 | D | 
| SCAN_F | 33 | F | 
| SCAN_G | 34 | G | 
| SCAN_H | 35 | H | 
| SCAN_J | 36 | J | 
| SCAN_K | 37 | K | 
| SCAN_L | 38 | L | 
| SCAN_Z | 44 | Z | 
| SCAN_X | 45 | X | 
| SCAN_C | 46 | C | 
| SCAN_V | 47 | V | 
| SCAN_B | 48 | B | 
| SCAN_N | 49 | N | 
| SCAN_M | 50 | M | 
| SCAN_F1 | 59 | F1 | 
| SCAN_F2 | 60 | F2 | 
| SCAN_F3 | 61 | F3 | 
| SCAN_F4 | 62 | F4 | 
| SCAN_F5 | 63 | F5 | 
| SCAN_F6 | 64 | F6 | 
| SCAN_F7 | 65 | F7 | 
| SCAN_F8 | 66 | F8 | 
| SCAN_F9 | 67 | F9 | 
| SCAN_F10 | 68 | F10 |