We will discuss about four file hacks listed as below-
- Rename – Rename a file using C/C++
- Remove – Remove a file using C/C++
- File Size – Get the file size using C/C++
- Check existence – Check whether a file exists or not in C/C++
C++
// C++ Program to demonstrate the // four file hacks every C/C++ must know // Note that we are assuming that the files // are present in the same file as the program // before doing the below four hacks #include <iostream> #include <stdlib.h> using namespace std;
// A Function to get the file size unsigned long long int fileSize( const char *filename)
{ // Open the file
FILE *fh = fopen (filename, "rb" );
fseek (fh, 0, SEEK_END);
unsigned long long int size = ftell (fh);
fclose (fh);
return size;
} // A Function to check if the file exists or not bool fileExists( const char * fname)
{ FILE *file;
if (file = fopen (fname, "r" ))
{
fclose (file);
return true ;
}
return false ;
} // Driver Program to test above functions int main()
{ cout << fileSize( "Passwords.txt" ) << " Bytes\n" ;
cout << fileSize( "Notes.docx" ) << " Bytes\n" ;
if (fileExists( "OldData.txt" ) == true )
cout << "The File exists\n" ;
else
cout << "The File doesn't exist\n" ;
rename ( "Videos" , "English_Videos" );
rename ( "Songs" , "English_Songs" );
remove ( "OldData.txt" );
remove ( "Notes.docx" );
if (fileExists( "OldData.txt" ) == true )
cout << "The File exists\n" ;
else
cout << "The File doesn't exist\n" ;
return 0;
} // This code is contributed by sarajadhav12052009 |
C
// A C Program to demonstrate the // four file hacks every C/C++ must know // Note that we are assuming that the files // are present in the same file as the program // before doing the below four hacks #include<stdio.h> #include<stdlib.h> #include<stdbool.h> // A Function to get the file size unsigned long long int fileSize( const char *filename)
{ // Open the file
FILE *fh = fopen (filename, "rb");
fseek (fh, 0, SEEK_END);
unsigned long long int size = ftell (fh);
fclose (fh);
return (size);
} // A Function to check if the file exists or not bool fileExists( const char * fname)
{ FILE *file;
if (file = fopen (fname, "r"))
{
fclose (file);
return ( true );
}
return ( false );
} // Driver Program to test above functions int main()
{ printf ("%llu Bytes\n", fileSize("Passwords.txt"));
printf ("%llu Bytes\n", fileSize("Notes.docx"));
if (fileExists("OldData.txt") == true )
printf ("The File exists\n");
else
printf ("The File doesn't exist\n");
rename ("Videos", "English_Videos");
rename ("Songs", "English_Songs");
remove ("OldData.txt");
remove ("Notes.docx");
if (fileExists("OldData.txt") == true )
printf ("The File exists\n");
else
printf ("The File doesn't exist\n");
return 0;
} |
Output:
Screenshot before executing the program :
Screenshot after executing the program :