📁C Files

In C, you can create, open, read, and write to files by declaring a pointer of type FILE, and use the fopen() function:

FILE *fptr
fptr = fopen(filename, mode); 

Here are the 3 modes you can specify:

w - Writes to a file
a - Appends new data to a file
r - Reads from a file 

Here is an example:

FILE *fptr;

// Create a file
fptr = fopen("filename.txt", "w");

// Close the file
fclose(fptr); 

Writing to a file:

if you want to write to a file, you first specify the path and the W mode and use fprintf:

 FILE *fptr;

// Open a file in writing mode
fptr = fopen("filename.txt", "w");

// Write some text to the file
fprintf(fptr, "Some text");

// Close the file
fclose(fptr); 

if there is already content it will overwrite it, if you want to append, you use the a mode:

// Open a file in append mode
fptr = fopen("filename.txt", "a");

// Append some text to the file
fprintf(fptr, "\nHi everybody!");