This section contains some C library functions that you should learn to use for implementing the scrambler program.

The general pattern for reading from a file in C consists of two steps:

opening the file, then

reading the bytes in the file.

Why do we need to explicitly $$open$$ a file? Can$$t we just read it directly? Good questions $($assuming you actually are asking them$).$ You will find out more hopefully in CSE $120.$ The short answer is file descriptors.

Opening a file

The first function is fopen, you should use this function to open the input file $($argv$[2])$ for reading. The prototype for the fopen function is as follows: