| 頭文件 | 核心功能與典型函數/宏 |
|---|
ALLOC.H | 內存管理：malloc, free, calloc, realloc, farcalloc, farmalloc (大內存模型) |
ASSERT.H | 斷言宏：assert(expr)，調試時檢查前置條件 |
BIOS.H | IBM PC ROM BIOS 中斷調用：bioskey, biosdisk, biosprint |
CONIO.H | DOS 控制台 I/O：**非標準**，getch, kbhit, clrscr, gotoxy, textcolor, cprintf |
CTYPE.H | 字符分類/轉換：isalpha, isdigit, isspace, toupper, tolower, toascii |
DIR.H | 目錄/路徑操作：mkdir, rmdir, chdir, getcwd, findfirst, findnext |
DOS.H | DOS 系統調用/中斷：int86, intdos, gettime, setdate, REGS, SREGS |
ERRNO.H | 錯誤碼助記符：EDOM, ERANGE, ENOMEM, EINVAL 等 |
FCNTL.H | 文件控制選項：O_RDONLY, O_WRONLY, O_CREAT, O_BINARY (open 參數) |
FLOAT.H | 浮點特性常量：FLT_MAX, DBL_EPSILON, FLT_DIG |
GRAPHICS.H | BGI 圖形庫：initgraph, closegraph, line, circle, setcolor, floodfill |
IO.H | 低級 I/O：open, close, read, write, lseek, tell, eof |
LIMITS.H | 整數類型極限：INT_MAX, CHAR_BIT, LONG_MIN, UINT_MAX |
MATH.H | 數學函數：sin, cos, tan, sqrt, pow, log, exp, fabs, ceil, floor, HUGE_VAL |
MEM.H | 內存操作 (多與 STRING.H 重疊)：memcpy, memset, memcmp, memchr, movmem |
PROCESS.H | 進程控制：spawn..., exec..., _exit, getpid |
SETJMP.H | 非局部跳轉：setjmp, longjmp, jmp_buf |
SHARE.H | 文件共享模式：SH_COMPAT, SH_DENYRW, SH_DENYWR, SH_DENYRD, SH_DENYNO |
SIGNAL.H | 信號處理：signal, raise, SIG_DFL, SIG_IGN, SIGINT, SIGTERM |
STDARG.H | 可變參數：va_list, va_start, va_arg, va_end (vprintf 等實現基礎) |
STDDEF.H | 標準定義：NULL, offsetof, size_t, ptrdiff_t, wchar_t |
STDIO.H | 標準 I/O 庫：printf, scanf, fopen, fclose, fread, fwrite, fseek, stdin/stdout/stderr |
STDLIB.H | 實用程序：malloc, free, exit, abort, atexit, qsort, bsearch, abs, labs, strtol, rand, srand |
STRING.H | 字符串操作：strcpy, strncpy, strcat, strcmp, strncmp, strlen, strchr, strstr, strtok, memset, memcpy, memmove |
SYS\STAT.H | 文件狀態：stat, fstat, S_IFMT, S_IFREG, S_IFDIR, S_IRUSR, S_IWUSR |
SYS\TYPES.H | 基本系統類型：time_t, off_t, ino_t, dev_t, pid_t |
SYS\TIME.H | 時間類型：time_t, struct timeb (ftime) |
TIME.H | 時間轉換：asctime, ctime, gmtime, localtime, strftime, difftime, clock, struct tm |
VALUE.H | 機器相關極限常量：MAXLONG, MAXDOUBLE, HIBITS, FLOAT_MAX |
