C/stdio.h/fclose

//Declaration :  int fclose(FILE *stream);
//Return value:  If successful, zero is returned, or EOF is returned.

  #include <stdio.h>
  #include <stdlib.h>
  int main(void)
  {
    FILE *fp;
    if((fp=fopen("test", "rb"))==NULL) {
      printf("Cannot open file.\n");
      exit(1);
    }
    if(fclose(fp))
        printf("File close error.\n");
    return 0;
  }