@var{buffer}. Returns the number of bytes actually read (0 at end of
file), or -1 if the file could not be read (due to a condition other
than end of file). Fd 0 reads from the keyboard using
@var{buffer}. Returns the number of bytes actually read (0 at end of
file), or -1 if the file could not be read (due to a condition other
than end of file). Fd 0 reads from the keyboard using