#include"stdio.h"
main()
{

    FILE *fp;
    if((fp=fopen("c1.txt","rt"))==NULL)
    {   printf("\nCannot open file!");
        getch();exit(1);
    }
    ch=fgetc(fp); 
    while(ch!=EOF) 
    {
        putchar(ch);                                
        ch=fgetc(fp);
    }
    fclose(fp); 

}

#include"stdio.h"
main()
{

    FILE *fp;
    char ch;
    if((fp=fopen("c2.txt",“wt"))==NULL)
    {   printf("\nCannot open file!");
        getch();exit(1);
    }
    ch=getchar(); 
    while (ch!=‘\n‘) 
    {   fputc(ch,fp); 
        ch=getchar();
    }
    fclose(fp); 


}

#include"stdio.h"
main()
{

    FILE *fp;
    char str[11];
    if((fp=fopen("c2.txt","rt"))==NULL)
    {   printf("\nCannot open file!");
        getch();
        exit(1);
    }
    fgets(str,4,fp);            
    printf("%s\n",str); 
    fclose(fp);

}

#include"stdio.h"
main()
{

    FILE *fp;
    char st[20];
    if((fp=fopen("c2.txt",“at+"))==NULL)
    {   printf("\nCannot open file!");
        getch();
        exit(1);
    }
    gets(st); 
    fputs(st,fp); 
    fclose(fp);

}