Create a text file and enter “to write a good program is very time consuming job.”. Create another text file which contains reverse of above text.

Solution:

#include<stdio.h>

#include<conio.h>

#include<stdlib.h>

void main()

{

FILE *in,*out;

char ch,f1[80],f2[80];

long loc;

clrscr();

printf("\n Enter Name of Source File:");

scanf("%s",&f1);

printf("\n Enter Name of Target File:");

scanf("%s",&f2);

in=fopen(f1,"w");

if(f1==NULL)

{

printf("\nCannot open file");

exit(0);

}

else

{

printf("\nEnter data in file %s(Press q to stop):",f1);

while(1)

{

ch=getchar();

if(ch=='q')

break;

else

fputc(ch,in);

}

fclose(in);

}

in=fopen(f1,"r");

if(f1==NULL)

{

printf("\nfile does not exist");

exit(0);

}

out=fopen(f2,"w");

if(f2==NULL)

{

printf("\ncannot open file");

exit(0);

}

fseek(in, 0, SEEK_END);

loc = ftell(in);

loc = loc-1;

while(loc >= 0)

{

fseek(in, loc, SEEK_END);

ch = fgetc(in);

fputc(ch, out);

loc--;

}

printf("\nfile copied in reverse order successfully");

fcloseall();

getch();

}