Scieneer Common Lisp 1.3.9 online documentation

ext:write-bytes stream bytes &optional start end waitp[Function]

Attempt to write the bytes vector from the start to the end position to the stream, returning the number of bytes consumed. If waitp is true then wait until all bytes have been consumed before returning. When waitp is false, consume as many bytes as possible without blocking, returning the number of bytes consumed which may be zero. The bytes may be buffered in the stream output buffer. When less bytes are consumed than requested, the function ext:stream-waiting-file-descriptor may be called to find the file descriptor and directions blocked and when ready the function may be called again to continue the operation.