// PROTOTYPE int read(int fd, void* buf, size_t count)
Reads from a file. Reads occur at the current file position, see
lseek, and end at the current end-of-file.
fd: The file descriptor for the file, return from the
buf: Pointer to the buffer to read data from the file into.
count: Number of bytes to read to the file.
Returns the number of bytes read, which is typically
count unless the end-of-file is reached, in which case the number of bytes actually read is returned. The number of bytes may be 0 if already at the end-of-file.
On error, returns -1 and sets
errno. Some possible
errno values include: