buffPtr
to 0 and buffCnt
to 0. These will keep track of the current position in the internal buffer and the count of characters in the buffer, respectively.buff
of size 4.read
is called with buf
and n
, initialize a pointer ptr
to 0 to track the number of characters copied to buf
.ptr < n
, perform the following steps:
a. If buffPtr
is 0, call read4(buff)
to read characters into the internal buffer and update buffCnt
with the number of characters read.
b. If buffCnt
is 0, break the loop as there are no more characters to read.
c. While ptr < n
and buffPtr < buffCnt
, copy characters from buff
to buf
and increment both ptr
and buffPtr
.
d. If buffPtr
reaches buffCnt
, reset buffPtr
to 0 to indicate that the internal buffer is consumed and needs to be refilled on the next iteration.ptr
as the number of characters read into buf
.