fopen example in C

Header file: 

     stdio.h

Synopsis:

      FILE *fopen(const char *filename, const char *mode);

Description: 

    Opens the file and returns a stream on success, or NULL on failure.

fopen function C example:

  #include<stdio.h>

  #include<errno.h>

  #include<string.h>

  int main() {

        FILE *fp;

        char ch, *str;

        fp = fopen("file.txt", "r");

        if (fp == NULL) {

                /* returns error message corresponding to errno */

                str = strerror(errno);

                /* prints error message corresponding to errno */

                perror(str);

                return;

        }

        while ((ch = getc(fp)) != EOF)

                putchar(ch);

        fclose(fp);

        return 0;

  }

  Output:

  jp@jp-VirtualBox:~/$ ls

  a.out  fopen.c  file.txt

  jp@jp-VirtualBox:~/$ cat file.txt

  hello world
  hello world
  hello world

  jp@jp-VirtualBox:~/$ ./a.out

  hello world

  hello world
  hello world