C Language Common library file (header file, function library)

C Language Common library file (header file, function library)C System provides a wealth of system files, called library files. C's library file is divided into two categories, one is a file with the extension ". h", called the header file, which we have used many times in the previous include command. The ". h" file contains information such as constant definitions, type definitions, macro definitions, function prototypes, and various compilation selection settings. The other is the function library, including the various functions of the target code for the user to call in the program. Typically, when you call a library function in a program, you include the ". h" file where the function prototype resides before the call.
The full ". h" file for Turbo C is given below. Turbo C Header File:

header File	Description
Alloc.h	Describes memory management functions (allocation, deallocation, and so on).
Assert.h	Defines an assert debug macro.
Bios.h	Describes the various functions that call the IBM-PC ROM BIOS subroutine.
Conio.h	Describes the various functions that invoke the DOS console I/O subroutine.
Ctype.h	Contains name class information about character classifications and conversions (such as Isalpha, Toascii, and so on).
Dir.h	Contains structures, macro definitions, and functions for directories and paths.
Dos.h	Defines and describes some constants and functions that are called by Msdos and 8086.
Error.h	A mnemonic that defines the error code.
Fcntl.h	Defines the symbolic constants when connecting to the open Library subroutine.
Float.h	Contains some parameters and functions for floating-point operations.
Graphics.h	Describes the functions of the graphical function, the constant definition of the graphical error code, the various color values that are being used for different drivers, and some special structures that the function uses.
IO.h	Contains the structure and description of the low-level I/O subroutine.
Limit.h	Contains information about each environment parameter, compile time limit, number of ranges, and so on.
Math.h	Explain the mathematical operation function, also set the HUGE VAL macro, explains the Matherr and Matherr subroutine used special structure.
Mem.h	Describes some memory manipulation functions (most of which are also described in STRING.H).
Process.h	Describes the various functions of process management, spawn ... and exec ... The structure description of the function.
Setjmp.h	Defines the types of jmp buf used by the longjmp and setjmp functions to illustrate these two functions.
Share.h	Defines parameters for file share functions.
Signal.h	Defines Sig[zz (z] [zz)]ign and Sig[zz (z] [zz)]DFL constants, which describe RAJSE and signal two functions.
Stddef.h	A macro that defines the read function parameter table. (such as the Vprintf,vscarf function).
Stddef.h	Define some common data types and macros.
Stdio.h	Defines the types and macros of standards and extensions defined by Kernighan and Ritchie in Unix System V. Also defines standard I/O pre-defined streams: Stdin,stdout and stderr, which describe I/O stream subroutines.
Stdlib.h	Describes some of the commonly used subroutines: convert subroutines, search/Sort subroutines, and so on.
String.h	Describes some string operations and memory manipulation functions.
SYS\Stat.h	Defines some of the symbolic constants that are used when opening and creating files.
Sys\types.h	Describes the Ftime function and the TIMEB structure.
Sys\time.h	Defines the type of time Time[zz (Z] [ZZ)]t.
Time.h	Defines the structure of the time-conversion subroutine Asctime, localtime, and gmtime, the types used for CTime, Difftime, Gmtime, localtime, and Stime, and provides prototypes of these functions.
Value.h	Defines some important constants, including those that depend on machine hardware and some constants that are described for compatibility with Unix System V, including the range of floating-point and double-precision values.

C Language Common library file (header file, function library)