Showing posts with label Program for fseeks() function in c. Show all posts
Showing posts with label Program for fseeks() function in c. Show all posts

Saturday, October 24, 2020

,

Example Program for FSEEK() function in c programming

 fseek() function in c programming is used to write data into desired file with the help of pointer which help to find the location into the given file.

Example Program for FSEEK()
Example Program for FSEEK() function in c programming

 

Syntax :-

int fseek(FILE *stream, long int offset, int whence)  

There are three constants are used in fseeks() function in c  SEEK_SET, SEEK_CUR and SEEK_END


 #include <stdio.h>
void main(){  
   FILE *fp;  
  
   fp = fopen("myfile.txt","w+");  
   fputs("This is functioinc", fp);  
    
   fseek( fp, 7, SEEK_SET );  
   fputs("Adam stiffman", fp);  
   fclose(fp);  
} 

Now let see the Example Program for FSEEK() function in c

#include <stdio.h>
int main ()
{
   FILE *f;
   char data[60];
   fp = fopen ("test.c","w");
   fputs("functioinc.in is a programming tutorial website", f);
   fgets ( data, 60, fp );
   printf(Before fseek - %s", data); 
 
   // To set file pointet to 21th byte/character into the file
   fseek(f, 21, SEEK_SET);
   fflush(data);
   fgets ( data, 60, fp );
   printf("After SEEK_SET to 21 - %s", data);
 
   // To find backward 10 bytes 
   fseek(f, -10, SEEK_CUR);
   fflush(data);
   fgets ( data, 60, fp );
   printf("After SEEK_CUR to -10 - %s", data);
 
   // To find 7th byte before the end of file
   fseek(f, -7, SEEK_END); 
   fflush(data);
   fgets ( data, 60, f );
   printf("After SEEK_END to -7 - %s", data);
 
   // now set file pointer to the start of the file
   fseek(f, 0, SEEK_SET); 
 
   fclose(f);
   return 0;
}