C Programming Tutorial
File Handling in c language is used to open, read, write, search or close file. It is used for permanent storage.
Advantage of File
It will contain the data even after program exit. Normally we use variable or array to store data, but data is lost after program exit. Variables and arrays are non-permanent storage medium whereas file is permanent storage medium.
Functions for file handling
There are many functions in C library to open, read, write, search and close file. A list of file functions are given below:
| No. | Function | Description |
|---|---|---|
| 1 | fopen() | opens new or existing file |
| 2 | fprintf() | write data into file |
| 3 | fscanf() | reads data from file |
| 4 | fputc() | writes a character into file |
| 5 | fgetc() | reads a character from file |
| 6 | fclose() | closes the file |
| 7 | fseek() | sets the file pointer to given position |
| 8 | fputw() | writes an integer to file |
| 9 | fgetw() | reads an integer from file |
| 10 | ftell() | returns current position |
| 11 | rewind() | sets the file pointer to the beginning of the file |
Opening File: fopen()
The fopen() function is used to open a file. The syntax of fopen() function is given below:
FILE *fopen( const char * filename, const char * mode );
You can use one of the following modes in the fopen() function.
| Mode | Description |
|---|---|
| r | opens a text file in read mode |
| w | opens a text file in write mode |
| a | opens a text file in append mode |
| r+ | opens a text file in read and write mode |
| w+ | opens a text file in read and write mode |
| a+ | opens a text file in read and write mode |
| rb | opens a binary file in read mode |
| wb | opens a binary file in write mode |
| ab | opens a binary file in append mode |
| rb+ | opens a binary file in read and write mode |
| wb+ | opens a binary file in read and write mode |
| ab+ | opens a binary file in read and write mode |
Closing File: fclose()
The fclose() function is used to close a file. The syntax of fclose() function is given below
int fclose( FILE *fp );
