C Language Learning

Learning C language is an interesting process. We can get a lot of fun and accomplishment from the book. In some typical C language books, we can see a lot of header text about C language. Now let's sort it out.

C system provides a wide range of system files, called library files. C library files are divided into two types, one is the extension ". h "file, called the header file, has been used many times in the preceding include command. The ". h" file contains constant definition, type definition, macro definition, function prototype, and various compilation and selection settings. Another type is the function library, which includes the target code of various functions for users to call in the program. When a library function is called in a program, the ". h" file of the function prototype must be included before the function is called.

The following describes all the ". h" files of Turbo C.

Turbo C header file

? ALLOC. H indicates memory management functions (such as allocation and release ).

? ASSERT. H defines assert debugging macros.

? BIOS. H describes the various functions that call the IBM-PC rom bios subroutine.

? CONIO. H indicates that each function of the I/O subprogram of the DOS console is called.

? CTYPE. H contains the name class information about character classification and conversion (such as isalpha and toascii ).

? DIR. H contains the Directory and path structures, macro definitions, and functions.

? DOS. H defines and describes some constants and functions called by MSDOS and 8086.

? ERRON. H defines the entrustment of the error code.

? FCNTL. H defines the symbolic constant used to connect to the open Library subroutine.

? FLOAT. H contains some parameters and functions related to floating point operations.

? GRAPHICS. H describes various functions related to graphic functions, constant definitions of graphic error codes, various color values of different drivers, and some special structures used by functions.

? IO. H contains the structure and description of low-level I/O subprograms.

? LIMIT. H contains environment parameters, compilation time limits, number ranges, and other information.

? MATH. H describes the mathematical operation functions, and defines the huge val macro, which describes the special structures used by matherr and matherr subprograms.

? MEM. H indicates some memory operation functions (most of them are also described in STRING. H ).

? PROCESS. H describes the various functions of PROCESS management, spawn... And EXEC... Function structure description.

? SETJMP. H defines the jmp buf types used by longjmp and setjmp functions.

? SHARE. H defines the parameters of the file sharing function.

? SIGNAL. H defines the SIG [ZZ (Z] [ZZ)] IGN and SIG [ZZ (Z] [ZZ)] DFL constants, indicating the rajse and signal functions.

? STDARG. H defines the macro of the read function parameter table. (Such as vprintf and vscscarf functions ).

? STDDEF. H defines some common data types and macros.

? STDIO. H defines the standard and extended types and macros defined by Kernighan and Ritchie in Unix System V. Standard I/O predefined streams: stdin, stdout, and stderr are also defined to describe the I/O Stream subprograms.

? STDLIB. H describes some common subprograms, such as conversion subprograms and search/sort subprograms.

? STRING. H describes some STRING operations and memory operation functions.

? SYS \ STAT. H defines some symbolic constants used to open and create files.

? SYS \ TYPES. H describes the ftime function and timeb structure.

? SYS \ TIME. H defines the time type TIME [ZZ (Z] [ZZ)] t.

? TIME. H defines the structure of the TIME conversion subprograms asctime, localtime, and gmtime, the types used by ctime, difftime, gmtime, localtime, and stime, and provides prototype of these functions.

? VALUE. H defines some important constants, including those dependent on machine hardware and which are described for compatibility with Unix System V, including floating point and double precision VALUE ranges.

There are still many header files in C language. You can continue to sort them tomorrow.