File Handling

Two files DATA1 and DATA2 contain sorted lists of integers. Write a C program to merge the contents of two files into a third file DATA i.e., the contents of the first file followed by those of the second are put in the third file.

Algorithm:

1. Open file1.txt and file 2.txt in reading mode. 

2. Open file3.txt in write mode. 

3. Run a loop to one by one copy characters of file1.txt to file3.txt. 

4. Run a loop to one by one copy characters of file2.txt to file3.txt. 

5. Close all files.

Program Code:

#include<stdio.h> 

void main() 

{ 

FILE *fp1, *fp2,*fp3; 

char ch; 

fp1=fopen("program.txt","r");

fp2=fopen("new.txt","r");

fp3=fopen("merge.txt","a"); 

if(fp1==NULL||fp2==NULL||fp3==NULL) 

{ 

printf("file opening problem"); 

return; 

} 

while(!feof(fp1)) 

{ 

ch=fgetc(fp1); 

fputc(ch,fp3); 

}

} 

Thanks

Mukesh Rajput