Hello Neil, Monday, September 10, 2007, 3:49:06 AM, you wrote:
I'm sure it's true, but it's quite irrelevant to my question, which is "why is using getChar so much slower than using getContents"?
Buffering, blocks and locks.
in ghc, is entirely due to locking, which is the slowest operation in whole hGetChar algorithm
Buffering: getChar demands to get a character now, which pretty much means you can't buffer.
both uses the same buffering (512 bytes)
Blocks: getContents reads blocks at a time from the underlying library, whereas getChar has to do one character at a time.
i don't see difference between buffering and blocking
Locks: getChar has to acquire locks, as does getContents. However, because getContents can operate on blocks, this requires many fewer locks.
getContents doesn't lock Handle because it is supposed to use it in exclusive manner -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com