Incrementally encodes or decodes (depending on this) an input stream by 'stepping' through a block of input at a time.
You should make sure outbuf is large enough by calling outlen to
find out how large outbuf might need to be.
| this |
a Encoding |
| inbuf |
an input buffer to encode or decode |
| inlen |
input buffer length |
| outbuf |
an output buffer |
|
the number of bytes written to |